Trauma Imaging Dr Dayea Oh Oral & Maxillofacial Radiologist    Dr Dayea Oh — Oral & Maxillofacial Radiologist Clinical photo: An intraoral view showing severe dental trauma, characterized by fractured and displaced anterior teeth with significant bleeding in the oral cavity. A composite image showing four panels (labeled A-D) of 3D reconstructed CT scans of a human skull, illustrating different types of mandibular fractures. Each panel displays the complete skull with a red rectangular overlay indicating the region of interest, and below it, an isolated view of the corresponding fracture or affected segment of the mandible. Clinical photograph showing an intraoral view of the maxillary anterior teeth and gingiva. The image depicts significant trauma to the upper front teeth, characterized by a deep horizontal fracture line across the middle third of the central incisor on the right (viewer's left) with exposed pulp tissue, and severe discoloration (brownish-red) of the adjacent central incisor indicating likely necrosis or hemorrhage. Gingival recession and swelling are visible around the fractured tooth, illustrating a complex dental injury involving both hard and soft tissues. # Objectives * Understand imaging goals in facial trauma * Review relevant maxillofacial anatomy on imaging * Compare CT, CBCT, and I/O radiographs - Understand imaging goals in facial trauma - Review relevant maxillofacial anatomy on imaging - Compare CT, CBCT, and I/O radiographs - Review ==imaging appearances of dental and facial injuries== - Compare ==periapical, occlusal, CBCT, and multislice CT imaging== Contents **Dento-alveolar trauma** • Injuries to dental structures • Injuries to supporting structures **When to use Cone Beam CT** **Facial Trauma & Multislice CT** #### Dento-alveolar trauma - Injuries to dental structures - Injuries to supporting structures #### When to use Cone Beam CT #### Facial Trauma & Multislice CT # Dento-alveolar trauma * **~5%** of all bodily injuries (all ages) * **15.5%** of patients aged between 7 and 20 had at least one traumatic dental injury to permanent dentition (Eilert-Petersson, 1997) * Primary dentition injury prevalence **22.7%** (Petti, Glendor and Andersson, 2018) * If trauma occurs at an age below 9 years, there is **8x risk for new trauma** (Glendor, 2007) - ~5% of all bodily injuries (all ages) - 15.5% of patients aged between 7 and 20 had at least one traumatic dental injury to permanent dentition (*Eilert-Petersson, 1997*) - Primary dentition injury prevalence 22.7% (*Petti, Glendor and Andersson, 2018*) - If trauma occurs at an age below 9 years, there is **8x risk for new trauma** (*Glendor, 2007*) > [!note] Lecturer — Epidemiology Details > The 1997 global study included more than 250,000 patients. A more recent global study reported a 15.2% prevalence of dental trauma in permanent dentition, based on a sample of 1 billion. A cartoon illustration of a boy falling from his bicycle, with the bike tumbling above him. The figure is depicted with an open mouth and hands reaching forward. Risk Factors • Increased overjet with protrusion of upper incisors • Insufficient lip closure • Behaviour • Risk-taking • Peer relationship problems • Attention-deficit hyperactivity disorder (ADHD) • Stress   - Increased overjet with protrusion of upper incisors - Insufficient lip closure - Behaviour - Risk-taking - Peer relationship problems - Attention-deficit hyperactivity disorder (ADHD) - Stress > [!note] Lecturer — Trauma Context > Dento-alveolar trauma involves injury to the teeth, periodontal tissues, alveolar bone, and adjacent soft tissues. It is common in young populations and is usually associated with accidents or interpersonal violence. - ==Peer relationship problems may include bullying== Clinical photo: A close-up view of the upper anterior teeth, specifically highlighting a fractured maxillary central incisor with a chipped incisal edge. The image illustrates the consequence of dental trauma, relevant to the listed risk factors such as increased overjet. A close-up photograph of a toddler with light hair and blue eyes wearing a novelty pacifier that features two large, white plastic teeth attached to the shield. The child is looking directly at the camera while holding their hands up in front of them. Classifications • More than 50 classifications (Andersson 2022) • **Modified Andreasen’s (by WHO) in 1994** • Most frequently used • Applies to both primary and permanent dentitions • International Association of Dental Traumatology (IADT) • American Association of Endodontists (AAE) - More than 50 classifications (*Andersson 2022*) - **Modified Andreasen's (by WHO) in 1994** - Most frequently used - Applies to both primary and permanent dentitions - International Association of Dental Traumatology (IADT) - American Association of Endodontists (AAE) > [!note] Lecturer — Classification History > The original Andreasen classification was published in 1981, and a later version was adopted by the WHO in 2022. The International Association of Dental Traumatology and the American Association of Endodontists have adopted this classification for their trauma guidance. WHO (Andreasen’s) I. Injuries to the hard dental tissues and the pulp II. Injuries to the periodontal tissues III. Injuries to the supporting bone IV. Injuries to gingiva or oral mucosa NOW: I. Hard tissues and Pulp Injuries II. Periodontal Injuries Textbook and Color Atlas of Traumatic Injuries to the Teeth 5th edition Edited by Jens O. Andreasen Frances M. Andreasen Lars Andersson WILEY Blackwell Dental Traumatology SHORT COMMUNICATION | Open Access | CC NA0D – The new Traumatic Dental Injury classification of the World Health Organization Stefano Petti, Jens Ove Andreasen, Ulf Glendor, Lars Andersson First published: 28 April 2022 | https://doi.org/10.1111/edt.12753 | VIEW METRICS   #### WHO (Andreasen's) I. Injuries to the hard dental tissues and the pulp II. Injuries to the periodontal tissues III. Injuries to the supporting bone IV. Injuries to gingiva or oral mucosa #### NOW I. Hard tissues and Pulp Injuries II. Periodontal Injuries #### Reference Sources *Textbook and Color Atlas of Traumatic Injuries to the Teeth, 5th edition. Edited by Jens O. Andreasen, Frances M. Andreasen, Lars Andersson. WILEY Blackwell.* *Dental Traumatology. SHORT COMMUNICATION | Open Access | CC. NA0D – The new Traumatic Dental Injury classification of the World Health Organization. Stefano Petti, Jens Ove Andreasen, Ulf Glendor, Lars Andersson. First published: 28 April 2022 | https://doi.org/10.1111/edt.12753* - ==The simplified classification combines periodontal tissues, supporting bone, and gingiva or oral mucosa into the second category== The image displays the front cover of a medical textbook. The title reads 'Textbook and Color Atlas of Traumatic Injuries to the Teeth 5th edition', edited by Jens O. Andreasen, Frances M. Andreasen, and Lars Andersson, published by Wiley Blackwell. The central visual is a photograph of a child wearing a helmet lying on pavement next to a skateboard, with an inset circular magnification showing an avulsed tooth on asphalt. A screenshot of a webpage featuring the IADT logo, navigation menus, and a grid of national flags labeled with languages (e.g., Spanish, Arabic, French) for selecting guideline translations. The page also includes clinical photos of dental injuries at the top and an image of a meeting in Dublin. I. Injuries to the hard dental tissues and the pulp        I. Injuries to the hard dental tissues and the pulp A labelled diagram of a tooth cross-section showing the enamel, dentin, pulp, and surrounding bone. A magnified circular inset highlights a fine crack line restricted to the outer surface of the enamel. This is a labelled diagram illustrating an enamel fracture. It shows a cross-section of a tooth with the crown intact except for a chip on the edge, and a magnified inset highlighting that the fracture line is confined to the outer white enamel layer without reaching the underlying dentin. A labelled anatomical diagram illustrating an enamel-dentin fracture in a tooth. The cross-sectional view depicts the outer enamel layer and underlying dentin chipped away on one side, exposing the internal pulp chamber. A labelled cross-sectional diagram of a tooth showing an Enamel-dentin-pulp fracture. The illustration depicts a vertical crack extending from the crown through the enamel and dentin layers, reaching into the central red pulp chamber. A cross-sectional anatomical diagram of a tooth root embedded in the jawbone, showing a fracture line extending through the enamel and dentin into the root structure without exposing the central pulp. A labelled anatomical diagram showing a vertical cross-section of a tooth embedded in alveolar bone. The illustration depicts a fracture line extending from the crown down through the root surface, exposing the internal pulp chamber and root canal (shown in red), which corresponds to the condition 'Crown-root fracture with pulp involvement'. Surrounding structures such as the cancellous bone and periodontal ligament space are also visible. A labelled anatomical diagram showing a longitudinal cross-section of a tooth embedded in the alveolar bone. The illustration depicts a fracture line across the root, separating the apex from the crown and mid-root structure. Tooth fracture patterns • Analysis of 33 fracture lines (of anterior teeth under direct frontal impacts) • Four common fracture patterns: • Horizontal crown fracture • Horizontal fracture at the neck of the tooth • Oblique crown-root fracture • Oblique root fracture  #### Tooth Fracture Patterns - Analysis of 33 fracture lines (of anterior teeth under direct frontal impacts) - Four common fracture patterns: - Horizontal crown fracture - Horizontal fracture at the neck of the tooth - Oblique crown-root fracture - Oblique root fracture > [!note] Lecturer — Fracture Detection > Two-dimensional imaging has reduced sensitivity for oblique fractures, which are more readily identified on CBCT. When the lips absorb part of the impact force, the forces may be distributed across multiple teeth and can result in concussion, subluxation, lateral luxation, or intrusion. A schematic line drawing of a tooth root overlaid with numerous white lines representing fracture patterns. The image illustrates the analysis of 33 specific fracture lines found in anterior teeth, showing the varied trajectories (horizontal and oblique) across the crown and root structure. II. Injuries to the periodontal tissues       II. Injuries to the periodontal tissues A cross-sectional diagram of a tooth embedded in the alveolar bone, illustrating the condition of concussion. The image depicts the root within the socket and shows redness and inflammation in the periodontal ligament space surrounding the root apex. A labelled anatomical diagram illustrating a tooth subluxation injury. The cross-section depicts the tooth root within the alveolar bone, with the periodontal ligament space appearing widened or disrupted to indicate the injury. A cross-sectional anatomical diagram illustrating an extrusion injury of a tooth. The image depicts the root and crown displaced vertically outward from the alveolar bone, showing separation from the surrounding periodontal tissues. A labelled anatomical diagram illustrating a lateral luxation injury, showing a tooth displaced laterally within the alveolar bone with associated damage to the surrounding periodontal tissues and gingiva. A cross-sectional diagram of a tooth showing an intrusion injury, where the crown is displaced apically into the alveolar bone. An anatomical illustration depicting an avulsed tooth completely separated from its socket in the alveolar bone. The image shows a cross-section of the jawbone with an empty socket and the detached tooth lying below it. “Radiographs are necessary to make a **thorough diagnosis** of dental injuries. Tooth root and bone fractures, for instance, may occur without any clinical signs or symptoms and are frequently undetected when only one radiographic view is used.” (IADT, 2020) **International Association of Dental Traumatology** > "Radiographs are necessary to make a **thorough diagnosis** of dental injuries. Tooth root and bone fractures, for instance, may occur without any clinical signs or symptoms and are frequently undetected when only one radiographic view is used." (IADT, 2020) International Association of Dental Traumatology Dental Traumatology COMPREHENSIVE REVIEW | Open Access International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 1. Fractures and luxations Cecilia Bourguignon, Nestor Cohenca, Eva Lauridsen, Marie Therese Flores, Anne C. O'Connell, Peter F. Day, Georgios Tsilingaridis, Paul V. Abbott, Ashraf F. Fouad, Lamar Hicks ... See all authors First published: 31 May 2020 | https://doi.org/10.1111/edt.12578 Since maxillary central incisors are the most frequently affected teeth, the radiographs listed below are recommended to thoroughly examine the injured area: 1. One parallel periapical radiograph aimed through the midline to show the two maxillary central incisors. 2. One parallel periapical radiograph aimed at the maxillary right lateral incisors (should also show the right canine and central incisor). 3. One parallel periapical radiograph aimed at the maxillary left lateral incisor (should also show the left canine and central incisor). 4. One maxillary occlusal radiograph. 5. At least one parallel periapical radiograph of the lower incisors centered on the two mandibular centrals. However, other radiographs may be indicated if there are obvious injuries of the mandibular teeth (eg, similar periapical radiographs as above for the maxillary teeth, mandibular occlusal radiograph).       *Dental Traumatology. COMPREHENSIVE REVIEW | Open Access. International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 1. Fractures and luxations. Cecilia Bourguignon, Nestor Cohenca, Eva Lauridsen, Marie Therese Flores, Anne C. O'Connell, Peter F. Day, Georgios Tsilingaridis, Paul V. Abbott, Ashraf F. Fouad, Lamar Hicks et al. First published: 31 May 2020 | https://doi.org/10.1111/edt.12578* Since maxillary central incisors are the most frequently affected teeth, the radiographs listed below are recommended to thoroughly examine the injured area: 1. One parallel periapical radiograph aimed through the midline to show the two maxillary central incisors. 2. One parallel periapical radiograph aimed at the maxillary right lateral incisors (should also show the right canine and central incisor). 3. One parallel periapical radiograph aimed at the maxillary left lateral incisor (should also show the left canine and central incisor). 4. One maxillary occlusal radiograph. 5. At least one parallel periapical radiograph of the lower incisors centered on the two mandibular centrals. However, other radiographs may be indicated if there are obvious injuries of the mandibular teeth (eg, similar periapical radiographs as above for the maxillary teeth, mandibular occlusal radiograph). > [!example] Maxillary Incisor Imaging Example > Clinical examination showed displacement of the left central incisor. The imaging series included one occlusal radiograph and three periapical radiographs; the occlusal view clearly demonstrated the displaced tooth and its socket, whereas one periapical view did not clearly demonstrate the displacement. A clinical close-up photograph showing the upper anterior teeth and gums, with fingers retracting the upper lip. The maxillary central incisors exhibit significant damage, characterized by white, opaque patches and roughened surfaces on the enamel crowns. Clinical photo: An intraoral view of the maxillary anterior teeth held open by a metal retractor. The central incisors exhibit distinct horizontal fractures involving the enamel and dentin, consistent with traumatic dental injuries. Radiograph: A periapical X-ray showing the maxillary central incisors and surrounding bone structure. The image illustrates the recommended radiographic examination for traumatic dental injuries, specifically focusing on the midline to visualize both central incisors. A periapical radiograph showing two maxillary central incisors with a horizontal root fracture visible in the left tooth (patient's right). The image illustrates the recommended radiographic examination for traumatic dental injuries, specifically highlighting the midline view. A periapical dental radiograph showing the maxillary anterior teeth, specifically focusing on the central incisors. The image displays the roots of the teeth and the surrounding alveolar bone structure. A periapical radiograph showing the maxillary anterior teeth, specifically focusing on the central and lateral incisors. The image reveals the roots of these teeth surrounded by bone trabeculae, with a notable radiolucent area visible near the apex of one tooth. | | CROWN FRACTURE | | CROWN/ROOT FRACTURE | ROOT FRACTURE | ALVEOLAR FRACTURE | | :--- | :--- | :--- | :--- | :--- | :--- | | **UNCOMPLICATED** | **COMPLICATED** | | | | | | **DEFINITION AND DIAGNOSIS** | Enamel and dentin fracture without pulp exposure. | Enamel and dentin fracture with pulp exposure. | A fracture involving enamel, dentin, and cementum with loss of tooth structure.<br>Crown fracture extends below gingival margin.<br>The pulp may or may not be exposed. | A fracture involving the root structure. It can be localized at the apical, middle or cervical third. | The bone segment containing the involved tooth/teeth is fractured and mobile. | | **CLINICAL ASSESMENT AND FINDINGS** | Sensitivity tests and vitality tests are likely to give positive results.<br>Normal mobility.<br>Percussion test: not tender. If tenderness is observed, evaluate the tooth for possible luxation or root fracture. | Sensitivity tests and vitality tests are likely to give positive results.<br>Exposed pulp sensitive to stimuli.<br>Normal mobility.<br>Percussion test: not tender. If tenderness is observed, evaluate the tooth for possible luxation or root fracture | Sensitivity tests and vitality tests are likely to give positive results.<br>Tender to percussion.<br>Coronal fragment is mobile. | The coronal fragment is usually mobile and sometimes displaced.<br>The apical segment is usually not displaced.<br>Tender to percussion.<br>Sensitivity tests may be initially negative indicating transient pulpal damage. | Fracture lines may be located at any level, from the marginal bone to the root apex.<br>Mobility of the teeth may be segmental if the fracture involves more than one alveolar socket.<br>Occlusal interference is often present due to misalignment of the fractured alveolar segment.<br>Displacement of an alveolar segment. | | **IMAGING AND RADIOGRAPHIC ASSESSMENT AND FINDINGS** | One occlusal and two periapical radiographs from mesial and distal are recommended in order to rule out displacement or the possible presence of a root fracture.<br>Radiograph of lip or cheek lacerations to search for tooth fragments or foreign material. | One occlusal and two periapical radiographs from mesial and distal are recommended in order to rule out displacement or the possible presence of a root fracture.<br>Radiograph of lip or cheek lacerations to search for tooth fragments or foreign material | One occlusal and two periapical radiographs from mesial and distal are recommended in order to rule out displacement or the possible presence of a root fracture.<br>CBCT should be considered to reveal the extension and direction of the fracture. | One occlusal radiograph to determine the level of the root fracture at the apical and middle third.<br>Two periapical radiographs with varying horizontal angles are needed to locate the fractures in the cervical third of the root.<br>For a root fracture in the middle third, CBCT may rule out or confirm an oblique course of fracture involving the cervical third in the labiolingual dimension. | In addition to the three angulations and occlusal film, additional views such as a panoramic radiograph can be helpful in determining the course and position of the fracture lines.<br>CBCT may be useful for diagnosis of alveolar fractures, especially when they involve the palatal or both cortical plates. |  #### Fracture Injuries — Definition, Clinical Findings, and Imaging | | CROWN FRACTURE (UNCOMPLICATED) | CROWN FRACTURE (COMPLICATED) | CROWN/ROOT FRACTURE | ROOT FRACTURE | ALVEOLAR FRACTURE | | :--- | :--- | :--- | :--- | :--- | :--- | | **Definition and diagnosis** | Enamel and dentin fracture without pulp exposure. | Enamel and dentin fracture with pulp exposure. | A fracture involving enamel, dentin, and cementum with loss of tooth structure. Crown fracture extends below gingival margin. The pulp may or may not be exposed. | A fracture involving the root structure. It can be localized at the apical, middle or cervical third. | The bone segment containing the involved tooth/teeth is fractured and mobile. | | **Clinical assessment and findings** | Sensitivity tests and vitality tests are likely to give positive results. Normal mobility. Percussion test: not tender. If tenderness is observed, evaluate the tooth for possible luxation or root fracture. | Sensitivity tests and vitality tests are likely to give positive results. Exposed pulp sensitive to stimuli. Normal mobility. Percussion test: not tender. If tenderness is observed, evaluate the tooth for possible luxation or root fracture. | Sensitivity tests and vitality tests are likely to give positive results. Tender to percussion. Coronal fragment is mobile. | The coronal fragment is usually mobile and sometimes displaced. The apical segment is usually not displaced. Tender to percussion. Sensitivity tests may be initially negative indicating transient pulpal damage. | Fracture lines may be located at any level, from the marginal bone to the root apex. Mobility of the teeth may be segmental if the fracture involves more than one alveolar socket. Occlusal interference is often present due to misalignment of the fractured alveolar segment. Displacement of an alveolar segment. | | **Imaging and radiographic assessment and findings** | One occlusal and two periapical radiographs from mesial and distal are recommended in order to rule out displacement or the possible presence of a root fracture. Radiograph of lip or cheek lacerations to search for tooth fragments or foreign material. | One occlusal and two periapical radiographs from mesial and distal are recommended in order to rule out displacement or the possible presence of a root fracture. Radiograph of lip or cheek lacerations to search for tooth fragments or foreign material. | One occlusal and two periapical radiographs from mesial and distal are recommended in order to rule out displacement or the possible presence of a root fracture. CBCT should be considered to reveal the extension and direction of the fracture. | One occlusal radiograph to determine the level of the root fracture at the apical and middle third. Two periapical radiographs with varying horizontal angles are needed to locate the fractures in the cervical third of the root. For a root fracture in the middle third, CBCT may rule out or confirm an oblique course of fracture involving the cervical third in the labiolingual dimension. | In addition to the three angulations and occlusal film, additional views such as a panoramic radiograph can be helpful in determining the course and position of the fracture lines. CBCT may be useful for diagnosis of alveolar fractures, especially when they involve the palatal or both cortical plates. | > [!note] Lecturer — CBCT Recommendations > The American Association of Endodontists recommends CBCT for crown-root fractures, root fractures, and alveolar fractures. It also suggests considering CBCT for most injury types, particularly luxation injuries and avulsions where alveolar fractures or other complications are more common. A clinical reference table comparing definitions, assessments, and radiographic findings for five types of dental fractures: Uncomplicated Crown Fracture, Complicated Crown Fracture, Crown/Root Fracture, Root Fracture, and Alveolar Fracture. Three specific recommendations regarding the use of CBCT imaging in the 'Imaging and Radiographic Assessment' row are highlighted with red hand-drawn circles. <table> <tr> <th></th> <th>CONCUSSION</th> <th>SUBLUXATION</th> <th>EXTRUSIVE LUXATION</th> <th>LATERAL LUXATION</th> <th>INTRUSIVE LUXATION</th> </tr> <tr> <td><b>DEFINITION AND DIAGNOSIS</b></td> <td>Tooth is tender to touch and/or percussion but without displacement or abnormal mobility.</td> <td>Tooth is tender to touch and/or percussion and mobile, but not displaced.</td> <td>Displacement of the tooth outward or incisally.</td> <td>Displacement of the tooth in any lateral direction except axially; usually associated with a fracture of the facial cortical bone.</td> <td>Displacement of the tooth inward and into the alveolar bone.</td> </tr> <tr> <td><b>CLINICAL ASSESMENT AND FINDINGS</b></td> <td>Sensitivity and vitality tests are likely to give positive results.<br>Tender to percussion.</td> <td>Sensitivity tests may be initially negative, indicating transient pulpal damage.<br>Vitality tests are likely to give positive results.<br>Tender to percussion.</td> <td>The tooth appears elongated and is excessively mobile.<br>Sensitivity and vitality tests are likely to give negative results<br>Tender to percussion.</td> <td>The tooth appears immobile or locked.<br>Fracture of the alveolar process may be palpable.<br>Sensitivity and vitality tests are likely to give negative results.<br>Tender to percussion.</td> <td>The tooth appears partially or totally infra-occluded, immobile and locked.<br>Fracture of the alveolar process may be palpable.<br>Sensitivity and vitality tests are likely to give negative results.<br>Tender to percussion.</td> </tr> <tr> <td><b>IMAGING AND RADIOGRAPHIC ASSESMENT AND FINDINGS</b></td> <td>Two periapical radiographs from mesial and distal to exclude displacement.<br>No radiographic abnormalities are expected.<br>CBCT should be considered if available and based on the severity of the injuries.</td> <td>Two periapical radiographs from mesial and distal to exclude displacement.<br>No radiographic abnormalities are expected.<br>CBCT should be considered if available and based on the severity of the injuries.</td> <td>One occlusal and two periapical radiographs from mesial and distal.<br>PDL space appears enlarged.<br>CBCT: evidence of increased PDL space and confirmation of the integrity of the socket, mainly on the sagittal and coronal planes.</td> <td>One occlusal and two periapical radiographs from mesial and distal.<br>PDL space appears enlarged.<br>CBCT: evidence of increased PDL space and diagnosis of alveolar fracture, mainly on the sagittal and coronal planes.</td> <td>One occlusal and two periapical radiographs from mesial and distal.<br>The periodontal ligament space may be absent from all or part of the root.<br>The cement-enamel junction is located more apically than the adjacent, non-injured teeth.<br>If the tooth is totally intruded, a lateral should be considered to evaluate the penetration into the nasal cavity.<br>CBCT: PDL space may be absent, mainly on the sagittal and coronal planes</td> </tr> </table> <b>Avulsion</b> <table> <tr> <td><b>IMAGING AND RADIOGRAPHIC ASSESMENT AND FINDINGS</b></td> <td>Two periapical radiographs from mesial and distal.<br>CBCT should be considered to confirm the reposition of the tooth and rule out alveolar bone fracture(s).</td> </tr> </table>  #### Luxation Injuries — Definition, Clinical Findings, and Imaging | | CONCUSSION | SUBLUXATION | EXTRUSIVE LUXATION | LATERAL LUXATION | INTRUSIVE LUXATION | | :--- | :--- | :--- | :--- | :--- | :--- | | **Definition and diagnosis** | Tooth is tender to touch and/or percussion but without displacement or abnormal mobility. | Tooth is tender to touch and/or percussion and mobile, but not displaced. | Displacement of the tooth outward or incisally. | Displacement of the tooth in any lateral direction except axially; usually associated with a fracture of the facial cortical bone. | Displacement of the tooth inward and into the alveolar bone. | | **Clinical assessment and findings** | Sensitivity and vitality tests are likely to give positive results. Tender to percussion. | Sensitivity tests may be initially negative, indicating transient pulpal damage. Vitality tests are likely to give positive results. Tender to percussion. | The tooth appears elongated and is excessively mobile. Sensitivity and vitality tests are likely to give negative results. Tender to percussion. | The tooth appears immobile or locked. Fracture of the alveolar process may be palpable. Sensitivity and vitality tests are likely to give negative results. Tender to percussion. | The tooth appears partially or totally infra-occluded, immobile and locked. Fracture of the alveolar process may be palpable. Sensitivity and vitality tests are likely to give negative results. Tender to percussion. | | **Imaging and radiographic assessment and findings** | Two periapical radiographs from mesial and distal to exclude displacement. No radiographic abnormalities are expected. CBCT should be considered if available and based on the severity of the injuries. | Two periapical radiographs from mesial and distal to exclude displacement. No radiographic abnormalities are expected. CBCT should be considered if available and based on the severity of the injuries. | One occlusal and two periapical radiographs from mesial and distal. PDL space appears enlarged. CBCT: evidence of increased PDL space and confirmation of the integrity of the socket, mainly on the sagittal and coronal planes. | One occlusal and two periapical radiographs from mesial and distal. PDL space appears enlarged. CBCT: evidence of increased PDL space and diagnosis of alveolar fracture, mainly on the sagittal and coronal planes. | One occlusal and two periapical radiographs from mesial and distal. The periodontal ligament space may be absent from all or part of the root. The cement-enamel junction is located more apically than the adjacent, non-injured teeth. If the tooth is totally intruded, a lateral should be considered to evaluate the penetration into the nasal cavity. CBCT: PDL space may be absent, mainly on the sagittal and coronal planes. | #### Avulsion | | IMAGING AND RADIOGRAPHIC ASSESSMENT AND FINDINGS | | :--- | :--- | | **Avulsion** | Two periapical radiographs from mesial and distal. CBCT should be considered to confirm the reposition of the tooth and rule out alveolar bone fracture(s). | > [!note] Lecturer — Luxation Imaging > Intraoral imaging has poor sensitivity for minimal displacement, root fractures, alveolar fractures, labial-palatal displacement, luxation injuries, and oblique or vertical fractures. CBCT can demonstrate displacement, periodontal ligament space changes, and associated bony injury more effectively. > [!note] Lecturer — Avulsion Follow-Up > For avulsion injuries, the IADT recommends radiographs immediately after replantation and during follow-up. The guideline does not explicitly recommend CBCT for every avulsion, whereas the AAE suggests considering it when alveolar fractures or other complications are suspected. A comparative reference table detailing five types of dental luxation injuries: Concussion, Subluxation, Extrusive Luxation, Lateral Luxation, and Intrusive Luxation. The rows categorize the information into 'Definition and Diagnosis', 'Clinical Assessment and Findings', and 'Imaging and Radiographic Assessment and Findings' for each injury type. Advantages of CBCT • No superimposition of anatomical structures • Dimensionally accurate (isotropic voxel) • Excellent spatial resolution • Small FOV + Voxel size (less than 0.1mm ideally) • Intraoral imaging has poor sensitivity in detecting minimal tooth displacement and root & alveolar fractures, especially: • **Labial / palatal tooth displacement (lateral luxation injuries)** • **Oblique & vertical root fractures** Voxel size 0.2 mm Voxel size 0.3 mm Voxel size 0.4 mm A B C D        #### Advantages of CBCT - No superimposition of anatomical structures - Dimensionally accurate (isotropic voxel) - Excellent spatial resolution - Small FOV + Voxel size (less than 0.1 mm ideally) - Intraoral imaging has poor sensitivity in detecting minimal tooth displacement and root & alveolar fractures, especially: - Labial / palatal tooth displacement (lateral luxation injuries) - Oblique & vertical root fractures *Voxel size 0.2 mm · Voxel size 0.3 mm · Voxel size 0.4 mm (panels A, B, C, D)* A grayscale sagittal cross-sectional radiographic image (CBCT slice) showing two teeth, likely an upper and lower incisor. The image illustrates the spatial relationship between the tooth roots and surrounding alveolar bone, with a horizontal black artifact or marker visible between the crowns. A grayscale CBCT scan slice showing a cross-section of the maxilla and mandible, with teeth visible in occlusion. A dark horizontal linear artifact extends from the right side, passing between the teeth. A grayscale cross-sectional radiographic image (likely a CBCT slice) showing a vertical view of a tooth root and surrounding bone. The image illustrates the effect of a larger voxel size, appearing grainier with less defined edges compared to higher resolution scans. A composite image showing a 3D volume rendering of a human skull with a red cylindrical overlay indicating the field of view, positioned above a corresponding 2D coronal slice reconstruction. A 3D reconstructed radiograph (CBCT) showing an anterior view of a human skull with a red cylindrical overlay indicating the field of view, and a separate cropped image below focusing on the maxilla and mandible to display the teeth and jaw structure. A 3D reconstructed skull image (likely from a CBCT scan) with a red rectangular volume of interest box highlighting the lower right mandibular region. Below it is a corresponding zoomed-in cross-sectional view showing teeth and bone structure within that selected area. A 3D reconstructed image of a human skull featuring red wireframe boxes overlaid on the lower jaw to illustrate different field-of-view (FOV) sizes, accompanied by an isolated rendering of the mandible below. CBCT vs PA in Horizontal Root Fractures? Dose Response. 2018 Jul-Sep; 16(3): 1559325818789837. Published online 2018 Aug 23. doi: 10.1177/1559325818789837 PMCID: PMC6108019 PMID: 30150907 Role of Computed Tomography Scan in Dental Trauma: A Cross-Sectional Study Feng Li,¹,* Jun Li,¹,* Deming Zhang,² and Feng Wu¹ Dentistry Research Article Open Access Hashemia, et al., Dentistry 2018, 8:9 DOI: 10.4172/2161-1122.1000513 Cone Beam Computed Tomography and Digital Periapical Radiography in Determining Horizontal Root Fractures: An In-vitro Comparative Study Seyed Mohsen Hashemia¹, Sanaz Jahadi², Shiva Shaygannia³, Ehsan Hekmatian⁴, Amirhosein Habibollahi⁵, Maryam Ghazizadeh⁶ • in vivo study #1 $\rightarrow$ CBCT has 98.8% sensitivity & 95.6% specificity (100 microns) & PA has 97.2% sensitivity & 78.5% specificity • Author states CBCT should be used for detection of **horizontal root fractures** • In vitro study #2 $\rightarrow$ CBCT (100microns) vs PA • “The sensitivity and specificity of CBCT radiography was **0.97 and 0.93**, and periapical was **0.83 and 0.885** respectively, indicating that the CBCT technique was preferred to the periapical to detect the **horizontal fracture** of the root” • “Although CBCT is an accurate imaging modality for detection of root fractures but based on ALARA (as low as reasonably achievable) it must be **used only for symptomatic patients that periapical images did not show any fractures**” #### CBCT Versus Periapical Radiography #### CBCT vs PA in Horizontal Root Fractures? *Li, F., Li, J., Zhang, D., and Wu, F. Role of Computed Tomography Scan in Dental Trauma: A Cross-Sectional Study. Dose Response. 2018 Jul-Sep; 16(3): 1559325818789837. Published online 2018 Aug 23. doi: 10.1177/1559325818789837. PMCID: PMC6108019. PMID: 30150907.* *Hashemia, S. M., Jahadi, S., Shaygannia, S., Hekmatian, E., Habibollahi, A., and Ghazizadeh, M. Cone Beam Computed Tomography and Digital Periapical Radiography in Determining Horizontal Root Fractures: An In-vitro Comparative Study. Dentistry 2018, 8:9. DOI: 10.4172/2161-1122.1000513.* - In vivo study #1 → CBCT has 98.8% sensitivity & 95.6% specificity (100 microns) & PA has 97.2% sensitivity & 78.5% specificity - Author states CBCT should be used for detection of **horizontal root fractures** - In vitro study #2 → CBCT (100 microns) vs PA - "The sensitivity and specificity of CBCT radiography was **0.97 and 0.93**, and periapical was **0.83 and 0.885** respectively, indicating that the CBCT technique was preferred to the periapical to detect the **horizontal fracture** of the root" - "Although CBCT is an accurate imaging modality for detection of root fractures but based on ALARA (as low as reasonably achievable) it must be **used only for symptomatic patients that periapical images did not show any fractures**" > [!note] Lecturer — Periapical Limitations > Periapical radiography may fail to show complex or multi-plane injuries. > > - Oblique fractures and associated alveolar injury may be missed. > - Internal resorption may also be difficult to identify. > - CBCT demonstrates the three-dimensional relationship between the tooth, root fracture, alveolar bone, periodontal ligament space, and root canal. - ==The 2018 study involved 250 cases.== A circular blue and white logo for the journal 'Dentistry', featuring a central tooth icon with a crack inside a solid circle, surrounded by the journal title at the top and its ISSN number at the bottom. PA vs CBCT CBCT Application in Dentoalveolar Trauma February 14, 2018 by Yosef Nahmias, DDS, MSc; Ali Fatemi, DDS, MSc, FRCD(C)   #### PA vs CBCT - CBCT Application in Dentoalveolar Trauma - February 14, 2018 - by Yosef Nahmias, DDS, MSc; Ali Fatemi, DDS, MSc, FRCD(C) > [!note] Lecturer — Periapical Projections > Periapical radiographs remain important for initial and follow-up imaging. > > - Multiple periapical projections and an occlusal projection are recommended because a fracture or displacement may be visible in one view but not another. > - CBCT provides additional information when two-dimensional imaging is inconclusive or a more complex injury is suspected. A periapical radiograph showing the upper anterior teeth, with a white arrow pointing to the root of a central incisor. The image illustrates an oblique root fracture that is difficult to detect on this 2D view. Radiograph: A grayscale cross-sectional dental image (likely a CBCT slice) showing a tooth root embedded in bone. Two white block arrows point to distinct linear radiolucent lines traversing the root structure, highlighting the fracture sites.      Clinical photograph showing the anterior maxillary teeth with a flexible metal splint bonded across the facial surfaces of the central and lateral incisors using composite resin. Clinical photograph of a patient's mouth showing the maxillary anterior teeth with severe gingival inflammation, characterized by bright red, swollen gum tissue and apparent bleeding at the margins. The upper lip is retracted with tape to expose the affected area. A periapical radiograph showing the maxillary anterior teeth, including central and lateral incisors. The image reveals radiopaque restorations on the crowns of the visible incisors and a curved radiopaque object (likely an archwire or appliance component) superimposed across the lower portion of the teeth. A sagittal cone-beam computed tomography (CBCT) image of the temporomandibular joint region, showing the mandibular condyle and glenoid fossa. Two white block arrows point to a linear radiolucent defect or fracture line within the bone of the condylar neck/head area. A cross-sectional dental radiograph (CBCT) showing the anterior maxilla and developing tooth buds. Two white arrows point to specific anatomical structures within the image. Summary: When to Take CBCT? • Acute Stage (compliant patient only) • **Symptomatic patients that periapical images did not show any fractures** • **Accurate assessment of root fractures & luxation injuries** • Late Stage • Review healing • “clinical and 2D radiographic examinations may not be sufficient to determine the presence or absence of pulp and periodontium healing” • Necrotic Pulp • Root resorption COMPREHENSIVE REVIEW | Free Access Contemporary imaging for the diagnosis and treatment of traumatic dental injuries: A review Nestor Cohenca, Adrian Silberman First published: 20 March 2017 | https://doi.org/10.1111/edt.12339 | Citations: 16 #### Indications for CBCT **Summary: When to Take CBCT?** - Acute Stage (compliant patient only) - Symptomatic patients that periapical images did not show any fractures - Accurate assessment of root fractures & luxation injuries - Late Stage - Review healing - "clinical and 2D radiographic examinations may not be sufficient to determine the presence or absence of pulp and periodontium healing" - Necrotic Pulp - Root resorption *Cohenca, N., and Silberman, A. Contemporary imaging for the diagnosis and treatment of traumatic dental injuries: A review. First published: 20 March 2017. https://doi.org/10.1111/edt.12339.* - ==CBCT also assists with crown-root fractures and alveolar fractures, including luxation or avulsion injuries with possible bony complications.== - ==At follow-up, CBCT may also show ankylosis, inflammation, and infection.== # Responses of the pulp, periradicular and soft tissues following trauma to the permanent teeth CY Yu,* PV Abbott* *School of Dentistry, The University of Western Australia, Western Australia, Australia.* **Table 1. Possible responses of the pulp and root canal system, the periradicular tissues, and the soft tissues following trauma to a tooth** | | Pulp/root canal system | Periradicular tissues | Soft tissues | | :--- | :--- | :--- | :--- | | **Favourable responses** | Recovery and return to normal<br>Tertiary dentine formation<br>Pulp revascularization<br>Pulp fibrosis<br>Pulp canal calcification | Recovery and return to normal<br>Fibrous healing<br>Transient apical breakdown | Recovery and return to normal<br>Transient marginal breakdown<br>Fibrous healing (scar) | | **Unfavourable responses** | Chronic pulp inflammation (pulpitis)<br>Pulp necrobiosis with<br>Pulp necrosis<br>without infection, with infection<br>Infection of the root canal system<br>Internal root resorption surface, inflammatory, and/or replacement<br>Combinations of the above: *simultaneously and/or sequentially over time* | Cessation of root development<br>Disturbances to root development<br>Bone resorption crestal, apical, and/or lateral<br>External root resorption surface, inflammatory, replacement, and/or invasive<br>Ankylosis: with or without root resorption<br>Combinations of the above: *simultaneously and/or sequentially over time* | Loss of attachment/ permanent marginal breakdown<br>Gingival recession<br>Combinations of the above: *simultaneously and/or sequentially over time* |  *CY Yu, PV Abbott. School of Dentistry, The University of Western Australia, Western Australia, Australia.* #### Table 1. Possible responses of the pulp and root canal system, the periradicular tissues, and the soft tissues following trauma to a tooth | | Pulp/root canal system | Periradicular tissues | Soft tissues | | :--- | :--- | :--- | :--- | | **Favourable responses** | Recovery and return to normal; tertiary dentine formation; pulp revascularization; pulp fibrosis; pulp canal calcification | Recovery and return to normal; fibrous healing; transient apical breakdown | Recovery and return to normal; transient marginal breakdown; fibrous healing (scar) | | **Unfavourable responses** | Chronic pulp inflammation (pulpitis); pulp necrobiosis with pulp necrosis — without infection, with infection; infection of the root canal system; internal root resorption — surface, inflammatory, and/or replacement; combinations of the above: *simultaneously and/or sequentially over time* | Cessation of root development; disturbances to root development; bone resorption — crestal, apical, and/or lateral; external root resorption — surface, inflammatory, replacement, and/or invasive; ankylosis — with or without root resorption; combinations of the above: *simultaneously and/or sequentially over time* | Loss of attachment / permanent marginal breakdown; gingival recession; combinations of the above: *simultaneously and/or sequentially over time* | This table categorizes the potential biological outcomes of dental trauma into favourable and unfavourable responses across three anatomical regions: the pulp/root canal system, periradicular tissues, and soft tissues. It lists specific clinical sequelae such as tertiary dentine formation and fibrous healing under favourable responses, while detailing complications like pulp necrosis, external root resorption, and gingival recession under unfavourable responses. CBCT CASES Identify crown/root #s & injuries to periodontal structures Slight widening of the periodontal ligament spaces Fracture of the incisal edge Ref: Atlas of Oral and Maxillofacial Radiology By Bernard Koong  CBCT case: identify crown/root numbers and injuries to periodontal structures. - Slight widening of the periodontal ligament spaces - Fracture of the incisal edge *Ref: Atlas of Oral and Maxillofacial Radiology, Bernard Koong.* > [!note] Lecturer — Subluxation Findings > Trauma assessment should identify both dental fractures and periodontal injuries. In one example, an uncomplicated crown fracture without pulp involvement was associated with widened periodontal ligament spaces, particularly palatally and apically, but no visible alveolar fracture. These findings were consistent with an uncomplicated fracture associated with subluxation. This is a corrected sagittal CBCT image of an incisor tooth, illustrating acute traumatic injury. Red arrows point to specific findings labeled in the image: 'Slight widening of the periodontal ligament spaces' along the root and 'Fracture of the incisal edge' at the crown tip. # MPR Trauma to 22  MPR — trauma to 22. A composite image showing four views from a dental CBCT scan with multi-planar reconstruction (MPR). It includes a panoramic view in the top left and three orthogonal cross-sectional slices (axial, coronal, and sagittal) highlighting a specific tooth region. **Crown/Root Fracture ?** - Horizontal / Oblique / Vertical? - Extension? - Complicated or Uncomplicated? Changes to the PDL space? Bony fracture?   #### Crown/Root Fracture? - Horizontal / oblique / vertical? - Extension? - Complicated or uncomplicated? Changes to the PDL space? Bony fracture? > [!note] Lecturer — Fracture Assessment > CBCT may clarify whether an apparent crown fracture extends into the root and whether the pulp is involved. Corrected planes are necessary to assess the relationship between the fracture line and the tooth’s long axis. Radiograph: A sagittal cross-sectional view (likely a CBCT scan) showing an anterior tooth and surrounding bone. The image highlights the root structure within the alveolar bone, illustrating the anatomical context for evaluating potential fractures. Radiograph: A grayscale dental X-ray image showing the upper anterior teeth and surrounding bone structure, with a yellow 'S/P' label in the top left corner. The image highlights a distinct horizontal fracture line across the root of one tooth. **Anterior Mx Trauma (11 Injured)** R L  Anterior maxillary trauma (11 injured). Orientation markers: R / L. Radiograph: A panoramic dental X-ray (orthopantomogram) showing the maxilla, mandible, and dentition. The image reveals multiple bright radiopaque restorations or crowns on the posterior teeth of both arches, along with R and L orientation markers. **MPR** I L R P S R L A S P  MPR view. Orientation markers: I, S, P, A; R / L. A four-panel Multi-Planar Reconstruction (MPR) radiograph displaying cross-sectional views of the maxilla and an anterior tooth. The images illustrate a traumatic injury where the tooth root is driven into the alveolar bone, accompanied by a shattered appearance of the outer labial cortical plate. 11 vs 21 Crown/Root Fracture ? Changes to the PDL space? Bony fracture?    11 vs 21: - Crown/root fracture? - Changes to the PDL space? - Bony fracture? A sagittal CT scan (cone-beam or medical) of the head and neck region showing the maxilla, mandible, teeth, and cervical spine. A yellow crosshair cursor is positioned over the floor of the mouth/tongue base area, likely indicating a specific point of interest such as soft tissue swelling or a foreign body. The image displays two stacked sagittal cross-sectional scans, likely from a Cone Beam CT (CBCT), focusing on the anterior maxilla and mandible. The scans reveal the upper and lower central incisors in occlusion, with a yellow crosshair marker positioned near the root apex of the lower incisor. Anatomical structures such as the hard palate, nasal floor, tongue, and cervical spine are visible in profile. Sagittal CT scan of the head and neck region, showing the skull base, cervical spine, mandible, maxilla, teeth, tongue, and airway. mm R L Tick Dist: 2.0 mm -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90  Measurement: Tick Dist: 2.0 mm. Scale (mm): -90 to 90 in increments of 10. Orientation markers: R / L. > [!example] Complex Root Fractures > A 21-year-old patient presented with a loose maxillary incisor after trauma. The tooth was mobile, tender to palpation and percussion, and non-responsive to cold testing. Initial periapical radiography showed a horizontal fracture at the cervical third of the root; the tooth was splinted, but the patient missed the six-week review and returned four months later with pain. > > - CBCT showed an incomplete horizontal fracture at the alveolar crest and an oblique fracture extending from the palatal surface, sharing the horizontal fracture line and extending apically to the labial surface near the junction of the middle and apical thirds. > - Internal resorption involved the canal, and the internal resorption and complex fracture pattern were not evident on the initial periapical radiograph. This is a panoramic dental radiograph (orthopantomogram) displaying the maxillary and mandibular arches, including developing permanent teeth. The image features measurement overlays, with a horizontal millimeter scale at the bottom ranging from -90 to 90 and vertical crosshairs centered on the midline. **Assess tooth by tooth.** **11?** **21?** **22?**  Assess tooth by tooth: 11? 21? 22? > [!example] Palatal Displacement and Alveolar Fracture > A 47-year-old woman fell and traumatized the maxillary central and lateral incisors. Both teeth were displaced palatally and non-responsive to sensibility testing; soft tissue lacerations were sutured immediately, and radiographs were obtained after repositioning and splinting. > > - Periapial imaging showed whitening of the periodontal ligament space, so CBCT was ordered to exclude dento-alveolar fractures. > - CBCT demonstrated a mildly displaced bicortical alveolar fracture extending from the palatal cortex to the labial cortex and involving the periodontal ligament spaces. > - No root fractures were identified at four weeks, but the teeth remained non-responsive, became discolored, and underwent root canal therapy. A composite image displaying four sequential axial cross-sectional slices from a dental Cone Beam CT (CBCT) scan. The views illustrate the upper arch with teeth embedded in the alveolar bone, showing different levels of sectioning through the roots and crowns.   A series of five sequential sagittal cross-sectional images from a CBCT scan, showing the maxilla and teeth at different angles. The panels are numbered from -6.00 to 2.00 along the bottom edge. This figure presents a series of five sagittal cross-sectional radiographic images, likely from a Cone Beam CT (CBCT) scan. The slices are arranged sequentially and labeled with numerical values at the bottom (4.00 to 12.00), showing anatomical structures such as bone and teeth along with millimeter scale rulers on the left side.   Radiograph: A panoramic dental X-ray showing the maxilla and mandible with a digital measurement grid overlay. The image displays mixed dentition, including developing tooth roots in the lower jaw and erupted teeth in the upper jaw, along with R and L orientation markers. Radiograph: A series of three axial CT scans showing cross-sections of the mandible. The images display the dental arch and jawbone, with a metallic artifact visible on the right side in the first slice. MPR L R L I P S L A P  MPR view. Orientation markers: I, P, S; L, A, P; L / R. A four-panel Multiplanar Reconstruction (MPR) view from a dental CBCT scan, displaying the mandible and teeth in axial, coronal, and sagittal planes. The panels are annotated with yellow letter labels indicating orientation: 'L' and 'R' for Left and Right, 'I' for Inferior, 'P' for Posterior, 'S' for Superior, and 'A' for Anterior. -20.00 -18.00 -16.00 -14.00 -12.00 -10.00 -8.00 -6.00 -4.00 -2.00           Scale: -20.00, -18.00, -16.00, -14.00, -12.00, -10.00, -8.00, -6.00, -4.00, -2.00 > [!note] Lecturer — MPR Alignment > Multiplanar reformatting is important for dental trauma assessment, and the CBCT data should be manipulated to obtain the appropriate angle for the clinical question. For a specific tooth, the MPR planes are aligned with the long axis by moving and rotating the cross-cursor. The corrected coronal and sagittal views follow the tooth’s long axis, with the coronal view resembling a traditional periapical radiograph. > [!example] Incomplete Lateral Incisor Fracture > Corrected MPR views of the lateral incisor showed an incomplete horizontal root fracture at the cementoenamel junction extending from the labial surface to the pulp. The periodontal ligament spaces were normal, and no bony fracture was visible in the corrected sagittal or coronal views. A vertical cross-sectional slice, likely from a CBCT scan, displaying a U-shaped anatomical structure (resembling a mandible) with bright cortical bone and trabecular interior. The image is overlaid with yellow measurement rulers labeled 'mm' along the top and left axes. A cross-sectional radiographic image (likely a CBCT slice) showing a tooth root embedded in bone, with yellow millimeter scale bars along the top and left edges for measurement. A grayscale medical radiograph, specifically a sagittal cross-sectional view likely from a Cone Beam CT scan. The image displays a segment of bone with visible internal trabecular patterns and a dense outer cortical layer, accompanied by yellow millimeter measurement scales along the top and left edges. A grayscale medical scan, likely a sagittal cross-section from a CBCT or CT image, depicting the anterior region of a mandible. The image shows the curved bone structure with a bright, dense cortical outline and internal trabecular patterns, accompanied by yellow millimeter scale rulers along the top and left edges for measurement. The image displays a grayscale radiographic cross-section, likely a CBCT scan of the mandible. A yellow measurement scale with vertical tick marks is positioned along the top edge to provide spatial reference. A sagittal cross-sectional medical image (resembling a CBCT scan) showing the anatomy of a lower jaw segment, including the alveolar bone and tooth roots. The view is framed by yellow millimeter measurement scales on the top and left sides. A grayscale medical scan, likely a sagittal CT or CBCT view, depicting the bony structure of a mandible (lower jaw). The image shows the curved body and ramus of the jawbone with high-density white areas representing bone and darker regions for soft tissue or marrow, framed by yellow measurement rulers on the top and sides. A grayscale cross-sectional medical image, likely a micro-CT scan, depicting a vertical slice of an elongated anatomical structure with a dense outer cortical shell and a porous internal trabecular network. The specimen is oriented vertically against a dark background and includes yellow measurement rulers along the top and left edges to indicate scale in millimeters. Radiograph: A sagittal cross-sectional medical scan (likely CT) showing a curved bony structure, possibly part of the mandible or skull base, surrounded by soft tissue. Yellow measurement scales are visible along the top and right edges of the image. A sagittal cross-sectional medical image, likely a CT scan, showing the anatomy of a digit (finger or toe) with visible bone structure and internal tissue details.  Radiograph: A sagittal cross-sectional image of the jaws showing multiple teeth in occlusion, including erupted molars and premolars as well as developing tooth buds within the bone. Orientation markers 'S' (superior) and 'T' (towards) are visible along with a blue reference line at the bottom.   Axial CT scan of the maxillofacial region showing the dental arch, mandibular rami, and airway. The image is oriented with 'R' (Right) on the left side and 'L' (Left) on the right side. Radiograph: An axial CT scan slice of the head and neck region, showing cross-sections of the mandible, teeth, and cervical vertebrae. A yellow crosshair cursor is positioned over the right side of the oral cavity/mandibular area. Facial Bone Trauma <u>CT is Gold Standard</u> CT is the gold standard for imaging facial bone trauma. > [!note] Lecturer — CT and CBCT > CT was described as the gold standard for maxillofacial trauma because it provides a large field of view and excellent resolution of hard and soft tissues. > > - CBCT is ideal for dento-alveolar and jaw fractures, but has a restricted field of view, slower or more limited scanning considerations, poorer soft tissue evaluation, and more noise than CT. > - Facial trauma commonly results from road traffic accidents, assault, and falls. > - Plain radiographs remain useful in some situations, but complex trauma is limited by superimposition, low sensitivity, and two-dimensional imaging. Classification of Cranio-Maxillofacial Fractures | Table 5.1 Classification of Cranio-Maxillofacial fractures | | | :--- | :--- | | **Category** | **Types of fractures** | | Facial bone fractures | –Nasal bone fracture<br>–Orbital fractures:<br> * Orbital floor (“blowout”) fracture<br> * Orbital roof (“blow-in”) fracture<br> * Medial or lateral orbital wall fractures<br>–Zygomaticomaxillary complex fracture<br>–Zygomatic arch fracture | | Maxillary fractures (Le Fort classification) | –Le Fort I: Horizontal fracture of the maxilla<br>–Le Fort II: Pyramidal fracture involving the nasal bridge, maxilla, and orbital floor<br>–Le Fort III: Craniofacial disjunction involving the zygomatic arches and orbital walls | | Mandibular fractures | –Condylar fracture<br>–Coronoid process fracture<br>–Ramus fracture<br>–Angle of mandible fracture<br>–Body of mandible fracture<br>–Symphysis and parasymphysis fracture<br>–Alveolar process fracture | | Frontal bone and Sinus fractures | –Frontal sinus anterior wall fracture<br>–Frontal sinus posterior wall fracture | | NOE fractures | Fractures involving the nasal bridge, ethmoid bone, and medial orbital rim | | Cranial vault and Skull base fractures | –Linear skull fractures<br>–Basilar skull fractures |   **Table 5.1 — Classification of Cranio-Maxillofacial Fractures** | Category | Types of fractures | | :--- | :--- | | Facial bone fractures | - Nasal bone fracture<br>- Orbital fractures:<br> - Orbital floor ("blowout") fracture<br> - Orbital roof ("blow-in") fracture<br> - Medial or lateral orbital wall fractures<br>- Zygomaticomaxillary complex fracture<br>- Zygomatic arch fracture | | Maxillary fractures (Le Fort classification) | - Le Fort I: Horizontal fracture of the maxilla<br>- Le Fort II: Pyramidal fracture involving the nasal bridge, maxilla, and orbital floor<br>- Le Fort III: Craniofacial disjunction involving the zygomatic arches and orbital walls | | Mandibular fractures | - Condylar fracture<br>- Coronoid process fracture<br>- Ramus fracture<br>- Angle of mandible fracture<br>- Body of mandible fracture<br>- Symphysis and parasymphysis fracture<br>- Alveolar process fracture | | Frontal bone and sinus fractures | - Frontal sinus anterior wall fracture<br>- Frontal sinus posterior wall fracture | | NOE fractures | Fractures involving the nasal bridge, ethmoid bone, and medial orbital rim | | Cranial vault and skull base fractures | - Linear skull fractures<br>- Basilar skull fractures | > [!note] Lecturer — Le Fort Classification > Le Fort fractures are classified according to separation of the maxilla from the skull base, and a fracture of the pterygoid plates is required as a hallmark of a Le Fort injury. These high-impact injuries describe patterns of midfacial skeletal dissociation. > > - Le Fort I produces a floating palate through horizontal separation above the teeth. > - Le Fort II is a pyramidal fracture involving the nasal bridge and infraorbital rim. > - Le Fort III detaches the midface from the cranial base, and the higher the fracture line, the more severe the injury. A two-column table titled 'Table 5.1 Classification of Cranio-Maxillofacial fractures' listing fracture categories and their corresponding types. The categories include Facial bone fractures, Maxillary fractures (Le Fort classification), Mandibular fractures, Frontal bone and Sinus fractures, NOE fractures, and Cranial vault and Skull base fractures. A 3D reconstructed CT scan of a human skull in lateral profile, labelled with letters A through F indicating various anatomical landmarks. # Nasal Fractures   Nasal fractures Radiograph: An axial CT scan of the midface, specifically visualizing the nasal complex. Two red arrows point to the paired nasal bones, highlighting a fracture or displacement in the region. Clinical photo: A 3D volume-rendered CT scan of a human skull in frontal view, illustrating nasal fractures. Three red arrows point to the nasal bridge area, indicating the location of the fracture lines. # Orbital    Orbital fractures Coronal CT scan of the orbits showing a hyperdense foreign body (indicated by red arrows) located in the left orbit. The label 'HS' and blue arrow point to the hyoid sinus, an anatomical structure. Coronal CT scan of the head showing the orbits, paranasal sinuses, and cranial vault with multiple colored arrows indicating specific anatomical sites or abnormalities. Green arrows point to fractures in the calvarium, while red, blue, teal, and purple arrows highlight various structures within the orbital and maxillary regions. Axial CT scan of the orbits showing a soft tissue mass in the left orbit (indicated by red arrows) that is displacing the globe and compressing the ethmoid air cells (blue arrows). The label 'C' points to the region near the orbital apex or posterior medial aspect. Le Fort Fractures (Midface / Maxilla) Le Fort III level Le Fort II level Le Fort I level   Le Fort fractures (midface / maxilla), shown by level: - Le Fort III level - Le Fort II level - Le Fort I level A labelled anatomical diagram of a human skull showing the fracture lines for three types of Le Fort fractures. The labels identify the 'Le Fort III level' (blue dashed line), 'Le Fort II level' (red dashed line), and 'Le Fort I level' (light blue dashed line). A composite of three 3D CT reconstructions showing the skull in frontal and lateral views. The images illustrate a Le Fort III fracture, characterized by the separation of the midface from the cranial base at the zygomaticofrontal suture and nasofrontal region. Mandibular Fracture Mandibular fractures Frequency by location Coronoid process 2 % Condyle 30 % Ramus 3 % Angle 25 % Body 25 % Parasympheal / Mental 15 % F Gaillard 2009 @Radiopedia.org Spin: 60 Tilt: 0 P A RA   #### Mandibular Fractures — Frequency by Location - Coronoid process: 2% - Condyle: 30% - Ramus: 3% - Angle: 25% - Body: 25% - Parasymphysis / mental: 15% *F Gaillard, 2009, @Radiopedia.org* > [!example] Displaced Comminuted Ramus Fracture > CT showed a displaced oblique comminuted fracture of the right mandibular ramus involving the retromolar triangle. > > - Axial images showed the fracture, air around it, and traumatic socket changes. > - Sagittal images showed the fracture extending posteriorly toward the anterior region, an associated socket, a triangular bony fragment up to 13 mm, and involvement of the 48 socket without a root fragment. > - Coronal images showed the displaced fracture extending anteriorly toward the socket. > - Soft tissue windows demonstrated air bubbles, subcutaneous emphysema, and involvement of the masticator and parapharyngeal spaces. > - Hard tissue windows demonstrate bone more clearly, whereas soft tissue windows demonstrate soft tissue involvement more clearly. A labelled anatomical photograph of a human mandible with black lines demarcating specific regions to illustrate fracture frequency statistics. The visible labels identify the Condyle (30 %), Ramus (3 %), Angle (25 %), Body (25 %), and Parasymphyseal / Mental (15 %) areas. A 3D CT reconstruction of a skull in lateral view, showing the mandible and cervical spine. The image visualizes the complex anatomy of the jaw joint and ramus, with orientation markers (P, A) and technical settings (Spin: 60, Tilt: 0) visible on the screen.    Radiograph: A sagittal CT scan of the head and neck, showing bony structures including the skull base, cervical spine, and facial bones. Radiograph: A sagittal computed tomography (CT) scan of the head, specifically visualizing the temporomandibular joint (TMJ). The image displays the bony structures of the mandibular condyle and the temporal bone in a side profile view. A sagittal CT scan of the head and neck region, oriented with Anterior (A) to the left and Posterior (P) to the right. An orange arrow points to a vertical column of dark pockets within the soft tissue anterior to the cervical spine. 16:33:39 H 36s\3 CT VR Mag: 1.05 HFS R L 120.00 kV 27.00 mA Tilt: 0.00 FOV: 167.00 Thickness: 0.60 mm 10.00mm/div 10.00mm/div LeftButton : Rotate JPEGLossy:75 16:33:39 H 36s\3 CT VR Mag: 1.85 HFS P A 120.00 kV 27.00 mA Tilt: 0.00 FOV: 167.00 Thickness: 0.60 mm 5.00mm/div 5.00mm/div LeftButton : Rotate JPEGLossy:75    CT volume-rendered images (H 36s\3), HFS orientation. - Image 1: VR Mag: 1.05 — R / L markers; 120.00 kV, 27.00 mA, Tilt: 0.00, FOV: 167.00, Thickness: 0.60 mm; 10.00 mm/div; LeftButton: Rotate; JPEG Lossy: 75 - Image 2: VR Mag: 1.85 — P / A markers; 120.00 kV, 27.00 mA, Tilt: 0.00, FOV: 167.00, Thickness: 0.60 mm; 5.00 mm/div; LeftButton: Rotate; JPEG Lossy: 75 A 3D volume-rendered CT scan showing an anterior (frontal) view of a human skull, including the maxilla, mandible, teeth, and nasal cavity. The image includes orientation markers 'R' (Right) and 'L' (Left), along with technical data overlays such as 'CT', 'VR Mag: 1.05', and scale bars. A small orientation marker icon featuring a central letter 'A' surrounded by the letters 'R', 'L', and 'P'. This symbol indicates anatomical directions (Anterior, Right, Left, Posterior) for the medical imaging scan. A 3D volume-rendered CT scan showing a lateral view of the temporomandibular joint (TMJ) and mandibular condyle. The image includes orientation markers 'P' (Posterior), 'A' (Anterior), and 'F' (Frontal/Inferior) along with scale bars indicating 5.00mm divisions. 120.0kVp 38mA Tilt: 0.0deg R L R L   CT: 120.0 kVp, 38 mA, Tilt: 0.0 deg; R / L markers. An axial computed tomography (CT) scan of the head, displayed in a bone window setting. The image shows cross-sectional anatomy including the maxillary sinuses, nasal cavity, orbits, and skull base structures like the petrous bones. Radiograph: A sagittal cross-sectional image (likely a CBCT slice) of the human skull, displaying the temporomandibular joint, mandible, maxilla, teeth, and nasal cavity. AI in Trauma Imaging • AI applications: • Automated fracture detection (mandible, midface) • Triage in emergency settings • 3D reconstruction assistance • Deep learning (CNNs) improves detection accuracy • Limitations: • Training dataset bias • Limited generalizability REVIEW article Front. Artif. Intell., 05 January 2024 Sec. Medicine and Public Health Volume 6 - 2023 | https://doi.org/10.3389/frai.2023.1278529 A review on artificial intelligence for the diagnosis of fractures in facial trauma imaging Tuan D. Pham * S Simon B. Holmes Paul Coulthard Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom  - AI applications: - Automated fracture detection (mandible, midface) - Triage in emergency settings - 3D reconstruction assistance - Deep learning (CNNs) improves detection accuracy - Limitations: - Training dataset bias - Limited generalizability *REVIEW article. Front. Artif. Intell., 05 January 2024. Sec. Medicine and Public Health, Volume 6 - 2023 | https://doi.org/10.3389/frai.2023.1278529. A review on artificial intelligence for the diagnosis of fractures in facial trauma imaging. Tuan D. Pham, S. Simon B. Holmes, Paul Coulthard. Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom.* > [!note] Lecturer — AI Performance and Limits > The lecturer emphasized that AI performance varies by fracture type and dataset. > > - AI has demonstrated high sensitivity for detecting maxillofacial fractures on CT. > - Some studies show performance approaching that of experienced radiologists, particularly for mandibular fractures. > - In emergency triage, AI may flag suspected fractures for rapid review. > - Accuracy may be reduced in complex or comminuted fractures, and AI should support rather than replace clinical judgment. A circular headshot of a man wearing a suit, positioned next to his name 'Paul Coulthard'. This serves as an author identification graphic. ## Case: Anterior Maxillary Trauma Imaging ### Question **Scenario:** A patient presents with anterior maxillary trauma, and clinical examination reveals displacement of the left central incisor. **What's shown:** An occlusal radiograph and three periapical radiographs (right side, midline, and left side). **Consider:** What do the different radiographic views demonstrate regarding the displacement of the tooth, and why are multiple views necessary? ### Answer **Observations:** - The occlusal view clearly demonstrates the displacement of the left central incisor, showing the empty socket. - The periapical views do not necessarily show the displacement of the tooth as clearly as the occlusal view. **Reasoning:** Different intraoral radiographs provide different angles and perspectives of the teeth and surrounding structures. Relying on a single view may miss critical details like tooth displacement, which is why multiple views (one occlusal and three periapicals) are required to fully assess the injury. **Takeaway:** Multiple intraoral radiographic views are essential in dental trauma to capture different angles and accurately diagnose displacements or fractures that may be missed on a single image. ## Case: Maxillary Incisor Trauma Follow-up ### Question **Scenario:** A 21-year-old patient presents with a loose, mobile, and tender maxillary incisor (tooth 11) following trauma. The tooth is non-responsive to cold testing. An initial periapical radiograph is taken, a splint is placed, and the patient is scheduled for a 6-week follow-up but returns after 4 months due to pain. **What's shown:** An initial periapical radiograph and a follow-up CBCT scan taken at 4 months. **Consider:** What are the findings on the initial periapical radiograph compared to the 4-month follow-up CBCT? ### Answer **Observations:** - The initial periapical radiograph revealed a horizontal fracture at the cervical third of the root. - The 4-month follow-up CBCT showed multiple complex root fractures: an incomplete horizontal fracture at the alveolar crest, and an oblique fracture extending from the palatal surface to the labial surface at the junction of the middle and apical thirds. - Internal resorption involving the canal was also present on the CBCT. **Reasoning:** The initial 2D periapical radiograph only captured the horizontal cervical fracture. The 3D CBCT scan, taken later due to persistent pain, revealed a much more complex fracture pattern and internal resorption that were not evident on the initial 2D imaging. **Takeaway:** CBCT is highly beneficial for detecting complex, oblique, or multiple root fractures and complications like internal resorption that may be missed or not fully appreciated on initial 2D intraoral radiographs. ## Case: Palatal Displacement of Central Incisors ### Question **Scenario:** A 47-year-old female falls and presents with trauma to teeth 11 and 21. Both teeth are displaced palatally, non-responsive to sensibility tests, and associated with soft tissue lacerations that are sutured. Radiographs are taken after the teeth are repositioned and splinted. **What's shown:** A periapical radiograph and a CBCT scan. **Consider:** What do the periapical radiograph and CBCT reveal about the periodontal and alveolar structures, and what is the subsequent clinical course? ### Answer **Observations:** - The periapical radiograph shows whitening of the periodontal ligament (PDL) spaces of teeth 11 and 21. - The CBCT reveals a mildly displaced bicortical alveolar fracture extending from the palatal to the labial cortex, involving the PDL spaces, with no root fractures identified. - At the 4-week recall, teeth 11 and 21 remain non-responsive to sensibility tests and become discolored. **Reasoning:** While the 2D radiograph suggested PDL widening, the CBCT provided a definitive diagnosis of a bicortical alveolar fracture. The lack of response to sensibility tests and subsequent discoloration at the 4-week follow-up indicated pulp necrosis, necessitating root canal therapy. **Takeaway:** CBCT is valuable for ruling in or out dentoalveolar fractures following trauma, and clinical follow-up is critical to monitor for pulp necrosis requiring endodontic intervention. ## Case: Anterior Maxillary Trauma Imaging ### Question **Scenario:** A patient presents with anterior maxillary trauma, and clinical examination reveals displacement of the left central incisor. **What's shown:** An occlusal radiograph and three periapical radiographs (right side, midline, and left side). **Consider:** What do the different radiographic views demonstrate regarding the displacement of the tooth, and why are multiple views necessary?    ### Answer **Observations:** - The occlusal view clearly demonstrates the displacement of the left central incisor, showing the empty socket. - The periapical views do not necessarily show the displacement of the tooth as clearly as the occlusal view. **Reasoning:** Different intraoral radiographs provide different angles and perspectives of the teeth and surrounding structures. Relying on a single view may miss critical details like tooth displacement, which is why multiple views (one occlusal and three periapicals) are required to fully assess the injury. **Takeaway:** Multiple intraoral radiographic views are essential in dental trauma to capture different angles and accurately diagnose displacements or fractures that may be missed on a single image. ## Case: Maxillary Incisor Trauma Follow-up ### Question **Scenario:** A 21-year-old patient presents with a loose, mobile, and tender maxillary incisor (tooth 11) following trauma. The tooth is non-responsive to cold testing. An initial periapical radiograph is taken, a splint is placed, and the patient is scheduled for a 6-week follow-up but returns after 4 months due to pain. **What's shown:** An initial periapical radiograph and a follow-up CBCT scan taken at 4 months. **Consider:** What are the findings on the initial periapical radiograph compared to the 4-month follow-up CBCT?   ### Answer **Observations:** - The initial periapical radiograph revealed a horizontal fracture at the cervical third of the root. - The 4-month follow-up CBCT showed multiple complex root fractures: an incomplete horizontal fracture at the alveolar crest, and an oblique fracture extending from the palatal surface to the labial surface at the junction of the middle and apical thirds. - Internal resorption involving the canal was also present on the CBCT. **Reasoning:** The initial 2D periapical radiograph only captured the horizontal cervical fracture. The 3D CBCT scan, taken later due to persistent pain, revealed a much more complex fracture pattern and internal resorption that were not evident on the initial 2D imaging. **Takeaway:** CBCT is highly beneficial for detecting complex, oblique, or multiple root fractures and complications like internal resorption that may be missed or not fully appreciated on initial 2D intraoral radiographs. ## Case: Palatal Displacement of Central Incisors ### Question **Scenario:** A 47-year-old female falls and presents with trauma to teeth 11 and 21. Both teeth are displaced palatally, non-responsive to sensibility tests, and associated with soft tissue lacerations that are sutured. Radiographs are taken after the teeth are repositioned and splinted. **What's shown:** A periapical radiograph and a CBCT scan. **Consider:** What do the periapical radiograph and CBCT reveal about the periodontal and alveolar structures, and what is the subsequent clinical course?    ### Answer **Observations:** - The periapical radiograph shows whitening of the periodontal ligament (PDL) spaces of teeth 11 and 21. - The CBCT reveals a mildly displaced bicortical alveolar fracture extending from the palatal to the labial cortex, involving the PDL spaces, with no root fractures identified. - At the 4-week recall, teeth 11 and 21 remain non-responsive to sensibility tests and become discolored. **Reasoning:** While the 2D radiograph suggested PDL widening, the CBCT provided a definitive diagnosis of a bicortical alveolar fracture. The lack of response to sensibility tests and subsequent discoloration at the 4-week follow-up indicated pulp necrosis, necessitating root canal therapy. **Takeaway:** CBCT is valuable for ruling in or out dentoalveolar fractures following trauma, and clinical follow-up is critical to monitor for pulp necrosis requiring endodontic intervention. Case: Anterior Maxillary Trauma Imaging A A clinical close-up photograph showing the upper anterior teeth and gums, with fingers retracting the upper lip. The maxillary central incisors exhibit significant damage, characterized by white, opaque patches and roughened surfaces on the enamel crowns. B Clinical photo: An intraoral view of the maxillary anterior teeth held open by a metal retractor. The central incisors exhibit distinct horizontal fractures involving the enamel and dentin, consistent with traumatic dental injuries. E A periapical dental radiograph showing the maxillary anterior teeth, specifically focusing on the central incisors. The image displays the roots of the teeth and the surrounding alveolar bone structure. Oblique fracture undetected A periapical radiograph showing the upper anterior teeth, with a white arrow pointing to the root of a central incisor. The image illustrates an oblique root fracture that is difficult to detect on this 2D view. Oblique fracture undetected Radiograph: A grayscale cross-sectional dental image (likely a CBCT slice) showing a tooth root embedded in bone. Two white block arrows point to distinct linear radiolucent lines traversing the root structure, highlighting the fracture sites. A periapical radiograph showing the maxillary anterior teeth, including central and lateral incisors. The image reveals radiopaque restorations on the crowns of the visible incisors and a curved radiopaque object (likely an archwire or appliance component) superimposed across the lower portion of the teeth. Clinical photograph of a patient's mouth showing the maxillary anterior teeth with severe gingival inflammation, characterized by bright red, swollen gum tissue and apparent bleeding at the margins. The upper lip is retracted with tape to expose the affected area. A cross-sectional dental radiograph (CBCT) showing the anterior maxilla and developing tooth buds. Two white arrows point to specific anatomical structures within the image. ## Case: Tooth 22 Fracture and MPR Alignment ### Question **Scenario:** A patient presents with a fractured tooth 22. The initial assessment suggests an uncomplicated crown fracture with subluxation. **What's shown:** CBCT images utilizing Multiplanar Reformatting (MPR) aligned specifically to the long axis of tooth 22, showing corrected coronal and sagittal views. **Consider:** What specific fracture and periodontal findings are identified when the 3D data is manipulated to align with the long axis of the tooth? ### Answer **Observations:** - The corrected views reveal an incomplete horizontal fracture of the tooth 22 root at the cementoenamel junction (CEJ), extending from the labial surface to the pulp. - The PDL spaces appear normal. - No bony fractures are identified in the corrected sagittal or coronal views. **Reasoning:** By using MPR to align the imaging planes with the long axis of the specific tooth, the resulting corrected coronal view resembles a traditional periapical radiograph, allowing for precise diagnosis of the root fracture extent and assessment of the PDL spaces without the distortion of standard axial/coronal/sagittal planes. **Takeaway:** Multiplanar reformatting (MPR) aligned to the long axis of a tooth is essential in CBCT assessment to accurately diagnose root fractures and evaluate periodontal spaces. ## Case: Intrusive Injury to Tooth 11 and Crown Defect on Tooth 21 ### Question **Scenario:** A patient presents with trauma to tooth 11. An initial OPG is taken, followed by a CBCT with MPR for both teeth 11 and 21. **What's shown:** An initial OPG and follow-up CBCT with corrected coronal and sagittal planes for teeth 11 and 21, as well as a volume-rendered image. **Consider:** What do the OPG and CBCT reveal regarding the injury to tooth 11, and what is observed regarding the crown structure of tooth 21? ### Answer **Observations:** - The initial OPG shows tooth 11 located slightly superiorly with partly missing coronal tooth structure. - The CBCT volume-rendered and corrected views confirm an intrusive injury of tooth 11 with a mild uncomplicated crown fracture at the tip, widened PDL spaces, and a comminuted labial alveolar fracture with multiple bone fragments. - The corrected sagittal view of tooth 21 shows a missing crown structure resembling a missing veneer rather than a shear fracture, with no PDL space whitening or bony fracture. **Reasoning:** The OPG provided a preliminary view of the intrusion and coronal loss, but the CBCT with MPR allowed for precise evaluation of the intrusive displacement, the exact nature of the crown fracture, and the associated alveolar bone comminution. The appearance of tooth 21 requires clinical correlation to differentiate between a veneer loss and a true shear fracture. **Takeaway:** CBCT with MPR provides critical 3D detail for intrusive injuries and associated alveolar fractures that cannot be fully appreciated on a 2D OPG, while also aiding in the assessment of adjacent teeth. ## Case: Anterior Maxilla Trauma and Avulsion ### Question **Scenario:** A patient presents with trauma to the upper anterior teeth, specifically involving tooth 22. **What's shown:** A reconstructed panoramic CBCT image, axial views of the maxilla, and corrected sagittal views of the upper anterior teeth. **Consider:** What is the extent of the bony fractures and the status of the teeth in the anterior maxilla based on the multiplanar CBCT views? ## Case: Tooth 22 Fracture and MPR Alignment ### Question **Scenario:** A patient presents with a fractured tooth 22. The initial assessment suggests an uncomplicated crown fracture with subluxation. **What's shown:** CBCT images utilizing Multiplanar Reformatting (MPR) aligned specifically to the long axis of tooth 22, showing corrected coronal and sagittal views. **Consider:** What specific fracture and periodontal findings are identified when the 3D data is manipulated to align with the long axis of the tooth?    ### Answer **Observations:** - The corrected views reveal an incomplete horizontal fracture of the tooth 22 root at the cementoenamel junction (CEJ), extending from the labial surface to the pulp. - The PDL spaces appear normal. - No bony fractures are identified in the corrected sagittal or coronal views. **Reasoning:** By using MPR to align the imaging planes with the long axis of the specific tooth, the resulting corrected coronal view resembles a traditional periapical radiograph, allowing for precise diagnosis of the root fracture extent and assessment of the PDL spaces without the distortion of standard axial/coronal/sagittal planes. **Takeaway:** Multiplanar reformatting (MPR) aligned to the long axis of a tooth is essential in CBCT assessment to accurately diagnose root fractures and evaluate periodontal spaces. ## Case: Intrusive Injury to Tooth 11 and Crown Defect on Tooth 21 ### Question **Scenario:** A patient presents with trauma to tooth 11. An initial OPG is taken, followed by a CBCT with MPR for both teeth 11 and 21. **What's shown:** An initial OPG and follow-up CBCT with corrected coronal and sagittal planes for teeth 11 and 21, as well as a volume-rendered image. **Consider:** What do the OPG and CBCT reveal regarding the injury to tooth 11, and what is observed regarding the crown structure of tooth 21?    ### Answer **Observations:** - The initial OPG shows tooth 11 located slightly superiorly with partly missing coronal tooth structure. - The CBCT volume-rendered and corrected views confirm an intrusive injury of tooth 11 with a mild uncomplicated crown fracture at the tip, widened PDL spaces, and a comminuted labial alveolar fracture with multiple bone fragments. - The corrected sagittal view of tooth 21 shows a missing crown structure resembling a missing veneer rather than a shear fracture, with no PDL space whitening or bony fracture. **Reasoning:** The OPG provided a preliminary view of the intrusion and coronal loss, but the CBCT with MPR allowed for precise evaluation of the intrusive displacement, the exact nature of the crown fracture, and the associated alveolar bone comminution. The appearance of tooth 21 requires clinical correlation to differentiate between a veneer loss and a true shear fracture. **Takeaway:** CBCT with MPR provides critical 3D detail for intrusive injuries and associated alveolar fractures that cannot be fully appreciated on a 2D OPG, while also aiding in the assessment of adjacent teeth. ## Case: Anterior Maxilla Trauma and Avulsion ### Question **Scenario:** A patient presents with trauma to the upper anterior teeth, specifically involving tooth 22. **What's shown:** A reconstructed panoramic CBCT image, axial views of the maxilla, and corrected sagittal views of the upper anterior teeth. **Consider:** What is the extent of the bony fractures and the status of the teeth in the anterior maxilla based on the multiplanar CBCT views?    Case: Tooth 22 Fracture and MPR Alignment A composite image showing four views from a dental CBCT scan with multi-planar reconstruction (MPR). It includes a panoramic view in the top left and three orthogonal cross-sectional slices (axial, coronal, and sagittal) highlighting a specific tooth region. Radiograph: A grayscale dental X-ray image showing the upper anterior teeth and surrounding bone structure, with a yellow 'S/P' label in the top left corner. The image highlights a distinct horizontal fracture line across the root of one tooth. Radiograph: A sagittal cross-sectional view (likely a CBCT scan) showing an anterior tooth and surrounding bone. The image highlights the root structure within the alveolar bone, illustrating the anatomical context for evaluating potential fractures. Radiograph: A panoramic dental X-ray (orthopantomogram) showing the maxilla, mandible, and dentition. The image reveals multiple bright radiopaque restorations or crowns on the posterior teeth of both arches, along with R and L orientation markers. Intrusion (Intrusive Luxation injury) & Comminuted fracture of Labial Cortex A four-panel Multi-Planar Reconstruction (MPR) radiograph displaying cross-sectional views of the maxilla and an anterior tooth. The images illustrate a traumatic injury where the tooth root is driven into the alveolar bone, accompanied by a shattered appearance of the outer labial cortical plate. The image displays two stacked sagittal cross-sectional scans, likely from a Cone Beam CT (CBCT), focusing on the anterior maxilla and mandible. The scans reveal the upper and lower central incisors in occlusion, with a yellow crosshair marker positioned near the root apex of the lower incisor. Anatomical structures such as the hard palate, nasal floor, tongue, and cervical spine are visible in profile. A series of five sequential sagittal cross-sectional images from a CBCT scan, showing the maxilla and teeth at different angles. The panels are numbered from -6.00 to 2.00 along the bottom edge. This figure presents a series of five sagittal cross-sectional radiographic images, likely from a Cone Beam CT (CBCT) scan. The slices are arranged sequentially and labeled with numerical values at the bottom (4.00 to 12.00), showing anatomical structures such as bone and teeth along with millimeter scale rulers on the left side. Radiograph: A panoramic dental X-ray showing the maxilla and mandible with a digital measurement grid overlay. The image displays mixed dentition, including developing tooth roots in the lower jaw and erupted teeth in the upper jaw, along with R and L orientation markers. ### Answer **Observations:** - The panoramic and axial views show that tooth 22 is missing (avulsed), leaving an empty socket. - There is a labial fracture superior to the apex of tooth 21, continuing inferiorly to involve the PDL space of 21 and extending to the 22 avulsion socket. - A separate palatal fracture starts in the 21 region and extends to the 22 socket. - Tooth 11 shows PDL space widening and a labial fracture. **Reasoning:** By utilizing panoramic, axial, and corrected sagittal views, the full extent of the complex alveolar fractures can be traced. The fractures involve both the labial and palatal cortices, connecting the injuries around teeth 11 and 21 to the avulsion site of tooth 22. **Takeaway:** Multiplanar CBCT imaging is necessary to trace the full extent of complex alveolar fractures and their relationship to avulsed and adjacent teeth in the anterior maxilla. ## Case: Mandibular Avulsion and Compound Fracture ### Question **Scenario:** A patient presents with mandibular dental trauma involving the 42 to 44 region. **What's shown:** CBCT cross-sectional slices and MPR (corrected coronal and sagittal views) of the right mandible (quadrant 4). **Consider:** What are the findings regarding the status of teeth 42, 43, and 44, and what type of fracture is present? ### Answer **Observations:** - Teeth 42 and 44 are missing, compatible with avulsion injuries. Tooth 42 has a root remnant, and tooth 44 is an empty socket with a small bone piece. - Tooth 43 has undergone endodontic treatment, with no root or crown fracture, but shows widened labial PDL space and PDL space whitening. - There is a comminuted labial bone fracture involving the labial PDL space of tooth 43 and extending from the 44 to 42 region. **Reasoning:** The cross-sectional slices and MPR clearly identify the avulsed teeth and root remnants. The involvement of the PDL (a soft tissue) by the bony fracture classifies this as a compound fracture. **Takeaway:** CBCT is highly effective in identifying avulsed teeth, root remnants, and compound fractures where bony fractures extend into the periodontal soft tissues. ## Case: Complex Dental Alveolar Trauma ### Question **Scenario:** A patient presents with complex dental alveolar trauma involving multiple teeth on the right side of the face (16, 15, 14, 44, 46). **What's shown:** A CBCT-generated panoramic view, corrected sagittal views, and axial views. **Consider:** What specific types of fractures are identified on the different CBCT planes for the involved teeth? ### Answer **Observations:** - Tooth 16: Cuspal fracture of the distobuccal cusp. - Tooth 15: Vertical fracture running mesiodistally, involving the pulp (not seen on initial sagittal views). - Tooth 14: Horizontal/labial fracture near the pulp extending towards the mandible. - Tooth 44: Oblique fracture. - Tooth 46: Mesiolingual cuspal fracture. **Reasoning:** The panoramic and sagittal views initially show definite fractures, but the axial views provide crucial additional information, revealing the exact orientation (e.g., vertical vs. horizontal) and pulp involvement of the fractures that were not fully appreciated on the other planes. **Takeaway:** In complex multi-tooth trauma, axial CBCT views are essential to determine the precise orientation, extent, and pulp involvement of fractures that may be ambiguous on panoramic or sagittal views. ### Answer **Observations:** - The panoramic and axial views show that tooth 22 is missing (avulsed), leaving an empty socket. - There is a labial fracture superior to the apex of tooth 21, continuing inferiorly to involve the PDL space of 21 and extending to the 22 avulsion socket. - A separate palatal fracture starts in the 21 region and extends to the 22 socket. - Tooth 11 shows PDL space widening and a labial fracture. **Reasoning:** By utilizing panoramic, axial, and corrected sagittal views, the full extent of the complex alveolar fractures can be traced. The fractures involve both the labial and palatal cortices, connecting the injuries around teeth 11 and 21 to the avulsion site of tooth 22. **Takeaway:** Multiplanar CBCT imaging is necessary to trace the full extent of complex alveolar fractures and their relationship to avulsed and adjacent teeth in the anterior maxilla. ## Case: Mandibular Avulsion and Compound Fracture ### Question **Scenario:** A patient presents with mandibular dental trauma involving the 42 to 44 region. **What's shown:** CBCT cross-sectional slices and MPR (corrected coronal and sagittal views) of the right mandible (quadrant 4). **Consider:** What are the findings regarding the status of teeth 42, 43, and 44, and what type of fracture is present?    ### Answer **Observations:** - Teeth 42 and 44 are missing, compatible with avulsion injuries. Tooth 42 has a root remnant, and tooth 44 is an empty socket with a small bone piece. - Tooth 43 has undergone endodontic treatment, with no root or crown fracture, but shows widened labial PDL space and PDL space whitening. - There is a comminuted labial bone fracture involving the labial PDL space of tooth 43 and extending from the 44 to 42 region. **Reasoning:** The cross-sectional slices and MPR clearly identify the avulsed teeth and root remnants. The involvement of the PDL (a soft tissue) by the bony fracture classifies this as a compound fracture. **Takeaway:** CBCT is highly effective in identifying avulsed teeth, root remnants, and compound fractures where bony fractures extend into the periodontal soft tissues. ## Case: Complex Dental Alveolar Trauma ### Question **Scenario:** A patient presents with complex dental alveolar trauma involving multiple teeth on the right side of the face (16, 15, 14, 44, 46). **What's shown:** A CBCT-generated panoramic view, corrected sagittal views, and axial views. **Consider:** What specific types of fractures are identified on the different CBCT planes for the involved teeth?    ### Answer **Observations:** - Tooth 16: Cuspal fracture of the distobuccal cusp. - Tooth 15: Vertical fracture running mesiodistally, involving the pulp (not seen on initial sagittal views). - Tooth 14: Horizontal/labial fracture near the pulp extending towards the mandible. - Tooth 44: Oblique fracture. - Tooth 46: Mesiolingual cuspal fracture. **Reasoning:** The panoramic and sagittal views initially show definite fractures, but the axial views provide crucial additional information, revealing the exact orientation (e.g., vertical vs. horizontal) and pulp involvement of the fractures that were not fully appreciated on the other planes. **Takeaway:** In complex multi-tooth trauma, axial CBCT views are essential to determine the precise orientation, extent, and pulp involvement of fractures that may be ambiguous on panoramic or sagittal views. Case: Anterior Maxilla Trauma and Avulsion > Answer A four-panel Multiplanar Reconstruction (MPR) view from a dental CBCT scan, displaying the mandible and teeth in axial, coronal, and sagittal planes. The panels are annotated with yellow letter labels indicating orientation: 'L' and 'R' for Left and Right, 'I' for Inferior, 'P' for Posterior, 'S' for Superior, and 'A' for Anterior. -8.00 A grayscale medical scan, likely a sagittal cross-section from a CBCT or CT image, depicting the anterior region of a mandible. The image shows the curved bone structure with a bright, dense cortical outline and internal trabecular patterns, accompanied by yellow millimeter scale rulers along the top and left edges for measurement. -4.00 Radiograph: A sagittal cross-sectional medical scan (likely CT) showing a curved bony structure, possibly part of the mandible or skull base, surrounded by soft tissue. Yellow measurement scales are visible along the top and right edges of the image. Dental X-ray showing complex, multiple dentoalveolar trauma A cross-sectional CBCT scan of the jaw and teeth, featuring a mouse cursor and numerical labels at the bottom. Radiograph: An axial CT scan slice of the head and neck region, showing cross-sections of the mandible, teeth, and cervical vertebrae. A yellow crosshair cursor is positioned over the right side of the oral cavity/mandibular area. ## Case: Displaced Nasal Bone Fracture ### Question **Scenario:** A patient presents with facial trauma. **What's shown:** A CT scan of the nasal region. **Consider:** What are the findings regarding the nasal bone and adjacent structures? ### Answer **Observations:** - There is a visible fracture line with rotation of the nasal bone, indicating a displaced nasal bone fracture. - Mucosal changes are present in the adjacent ethmoid air cells. **Reasoning:** CT imaging clearly delineates the bony disruption and displacement of the nasal bone, as well as the secondary soft tissue/mucosal changes in the adjacent sinuses resulting from the trauma. **Takeaway:** CT is the gold standard for evaluating nasal bone fractures, allowing for the assessment of both bony displacement and associated mucosal changes. ## Case: Orbital Floor Blowout Fracture ### Question **Scenario:** A patient presents with facial trauma involving the orbit. **What's shown:** A CT image of the orbital region. **Consider:** What are the findings regarding the orbital floor and the paranasal sinuses? ### Answer **Observations:** - There is a defect in the orbital floor (blowout fracture). - There is hemisinus (blood accumulation) in both the left and right maxillary sinuses. **Reasoning:** The CT scan demonstrates the structural defect in the orbital floor, which can allow orbital contents to herniate into the sinus. The presence of bilateral hemisinus indicates bleeding into the sinuses, a common associated finding in orbital floor fractures. **Takeaway:** CT imaging is essential for identifying orbital floor blowout fractures and associated complications like hemisinus, which helps in assessing the severity and potential for muscle entrapment. ## Case: Right Mandibular Ramus Fracture ### Question **Scenario:** A patient presents with trauma to the right mandible. **What's shown:** CT axial, sagittal, coronal, and soft tissue window views of the right mandibular ramus. **Consider:** What are the characteristics of the fracture, and what soft tissue complications are visible on the soft tissue window? ### Answer **Observations:** - There is a displaced, oblique, comminuted bony fracture of the right mandibular ramus involving the retromolar triangle. - A small triangular bony fragment measuring 13 mm is present. - The fracture involves the tooth 48 socket without a root fragment. - The soft tissue window reveals subcutaneous emphysema (air bubbles) involving the masticator and parapharyngeal spaces. **Reasoning:** The hard tissue windows clearly define the complex, comminuted nature of the fracture and the involvement of the third molar socket. Switching to the soft tissue window is crucial for identifying the presence of air (subcutaneous emphysema) in the fascial spaces, indicating a communication with the oral cavity or airway. **Takeaway:** Utilizing both hard and soft tissue CT windows is critical in mandibular trauma to evaluate the bony fracture details and identify soft tissue complications like subcutaneous emphysema. ## Case: Displaced Condylar Fracture ### Question **Scenario:** A patient presents with mandibular trauma and dental malocclusion. **What's shown:** CT axial, coronal, and sagittal views of the mandibular condyle. **Consider:** What is the position of the fractured condylar head, and are there any associated findings? ### Answer **Observations:** - The fractured condylar head is displaced anteriorly (seen on axial), medially (seen on coronal), and inferior to the articular eminence (seen on sagittal). - There is minimal contact at the middle aspect of the condylar neck. - The mandibular symphysis is deviated to the left. - There is no contralateral fracture. **Reasoning:** Multiplanar CT imaging allows for precise 3D localization of the displaced condylar fragment. The displacement explains the symphysis deviation and the clinical finding of dental malocclusion. The absence of a contralateral fracture is noted as a rare but important finding, as mandibular fractures often occur in two locations. **Takeaway:** Multiplanar CT is necessary to accurately determine the 3D displacement of condylar fractures and assess for associated deviations or contralateral injuries. ## Case: Displaced Nasal Bone Fracture ### Question **Scenario:** A patient presents with facial trauma. **What's shown:** A CT scan of the nasal region. **Consider:** What are the findings regarding the nasal bone and adjacent structures?   ### Answer **Observations:** - There is a visible fracture line with rotation of the nasal bone, indicating a displaced nasal bone fracture. - Mucosal changes are present in the adjacent ethmoid air cells. **Reasoning:** CT imaging clearly delineates the bony disruption and displacement of the nasal bone, as well as the secondary soft tissue/mucosal changes in the adjacent sinuses resulting from the trauma. **Takeaway:** CT is the gold standard for evaluating nasal bone fractures, allowing for the assessment of both bony displacement and associated mucosal changes. ## Case: Orbital Floor Blowout Fracture ### Question **Scenario:** A patient presents with facial trauma involving the orbit. **What's shown:** A CT image of the orbital region. **Consider:** What are the findings regarding the orbital floor and the paranasal sinuses?    ### Answer **Observations:** - There is a defect in the orbital floor (blowout fracture). - There is hemisinus (blood accumulation) in both the left and right maxillary sinuses. **Reasoning:** The CT scan demonstrates the structural defect in the orbital floor, which can allow orbital contents to herniate into the sinus. The presence of bilateral hemisinus indicates bleeding into the sinuses, a common associated finding in orbital floor fractures. **Takeaway:** CT imaging is essential for identifying orbital floor blowout fractures and associated complications like hemisinus, which helps in assessing the severity and potential for muscle entrapment. ## Case: Right Mandibular Ramus Fracture ### Question **Scenario:** A patient presents with trauma to the right mandible. **What's shown:** CT axial, sagittal, coronal, and soft tissue window views of the right mandibular ramus. **Consider:** What are the characteristics of the fracture, and what soft tissue complications are visible on the soft tissue window?    ### Answer **Observations:** - There is a displaced, oblique, comminuted bony fracture of the right mandibular ramus involving the retromolar triangle. - A small triangular bony fragment measuring 13 mm is present. - The fracture involves the tooth 48 socket without a root fragment. - The soft tissue window reveals subcutaneous emphysema (air bubbles) involving the masticator and parapharyngeal spaces. **Reasoning:** The hard tissue windows clearly define the complex, comminuted nature of the fracture and the involvement of the third molar socket. Switching to the soft tissue window is crucial for identifying the presence of air (subcutaneous emphysema) in the fascial spaces, indicating a communication with the oral cavity or airway. **Takeaway:** Utilizing both hard and soft tissue CT windows is critical in mandibular trauma to evaluate the bony fracture details and identify soft tissue complications like subcutaneous emphysema. ## Case: Displaced Condylar Fracture ### Question **Scenario:** A patient presents with mandibular trauma and dental malocclusion. **What's shown:** CT axial, coronal, and sagittal views of the mandibular condyle. **Consider:** What is the position of the fractured condylar head, and are there any associated findings?    ### Answer **Observations:** - The fractured condylar head is displaced anteriorly (seen on axial), medially (seen on coronal), and inferior to the articular eminence (seen on sagittal). - There is minimal contact at the middle aspect of the condylar neck. - The mandibular symphysis is deviated to the left. - There is no contralateral fracture. **Reasoning:** Multiplanar CT imaging allows for precise 3D localization of the displaced condylar fragment. The displacement explains the symphysis deviation and the clinical finding of dental malocclusion. The absence of a contralateral fracture is noted as a rare but important finding, as mandibular fractures often occur in two locations. **Takeaway:** Multiplanar CT is necessary to accurately determine the 3D displacement of condylar fractures and assess for associated deviations or contralateral injuries. Case: Displaced Nasal Bone Fracture (a) Clinical photo: A 3D volume-rendered CT scan of a human skull in frontal view, illustrating nasal fractures. Three red arrows point to the nasal bridge area, indicating the location of the fracture lines. (a) Radiograph: An axial CT scan of the midface, specifically visualizing the nasal complex. Two red arrows point to the paired nasal bones, highlighting a fracture or displacement in the region. Coronal CT scan of the head showing the orbits, paranasal sinuses, and cranial vault with multiple colored arrows indicating specific anatomical sites or abnormalities. Green arrows point to fractures in the calvarium, while red, blue, teal, and purple arrows highlight various structures within the orbital and maxillary regions. Coronal CT scan of the orbits showing a hyperdense foreign body (indicated by red arrows) located in the left orbit. The label 'HS' and blue arrow point to the hyoid sinus, an anatomical structure. Axial CT scan of the orbits showing a soft tissue mass in the left orbit (indicated by red arrows) that is displacing the globe and compressing the ethmoid air cells (blue arrows). The label 'C' points to the region near the orbital apex or posterior medial aspect. Radiograph: A sagittal computed tomography (CT) scan of the head, specifically visualizing the temporomandibular joint (TMJ). The image displays the bony structures of the mandibular condyle and the temporal bone in a side profile view. Radiograph: A sagittal CT scan of the head and neck, showing bony structures including the skull base, cervical spine, and facial bones. A sagittal CT scan of the head and neck region, oriented with Anterior (A) to the left and Posterior (P) to the right. An orange arrow points to a vertical column of dark pockets within the soft tissue anterior to the cervical spine. A 3D volume-rendered CT scan showing a lateral view of the temporomandibular joint (TMJ) and mandibular condyle. The image includes orientation markers 'P' (Posterior), 'A' (Anterior), and 'F' (Frontal/Inferior) along with scale bars indicating 5.00mm divisions. An axial computed tomography (CT) scan of the head, displayed in a bone window setting. The image shows cross-sectional anatomy including the maxillary sinuses, nasal cavity, orbits, and skull base structures like the petrous bones. Radiograph: A sagittal cross-sectional image (likely a CBCT slice) of the human skull, displaying the temporomandibular joint, mandible, maxilla, teeth, and nasal cavity. [^1]: Original PDF page 1: [[L4 - Imaging for Trauma.pdf#page=1|L4 - Imaging for Trauma, p.1]] [^2]: Original PDF page 2: [[L4 - Imaging for Trauma.pdf#page=2|L4 - Imaging for Trauma, p.2]] [^3]: Original PDF page 3: [[L4 - Imaging for Trauma.pdf#page=3|L4 - Imaging for Trauma, p.3]] [^4]: Original PDF page 4: [[L4 - Imaging for Trauma.pdf#page=4|L4 - Imaging for Trauma, p.4]] [^5]: Original PDF page 5: [[L4 - Imaging for Trauma.pdf#page=5|L4 - Imaging for Trauma, p.5]] [^6]: Original PDF page 6: [[L4 - Imaging for Trauma.pdf#page=6|L4 - Imaging for Trauma, p.6]] [^7]: Original PDF page 7: [[L4 - Imaging for Trauma.pdf#page=7|L4 - Imaging for Trauma, p.7]] [^8]: Original PDF page 8: [[L4 - Imaging for Trauma.pdf#page=8|L4 - Imaging for Trauma, p.8]] [^9]: Original PDF page 9: [[L4 - Imaging for Trauma.pdf#page=9|L4 - Imaging for Trauma, p.9]] [^10]: Original PDF page 10: [[L4 - Imaging for Trauma.pdf#page=10|L4 - Imaging for Trauma, p.10]] [^11]: Original PDF page 11: [[L4 - Imaging for Trauma.pdf#page=11|L4 - Imaging for Trauma, p.11]] [^12]: Original PDF page 12: [[L4 - Imaging for Trauma.pdf#page=12|L4 - Imaging for Trauma, p.12]] [^13]: Original PDF page 13: [[L4 - Imaging for Trauma.pdf#page=13|L4 - Imaging for Trauma, p.13]] [^14]: Original PDF page 14: [[L4 - Imaging for Trauma.pdf#page=14|L4 - Imaging for Trauma, p.14]] [^15]: Original PDF page 15: [[L4 - Imaging for Trauma.pdf#page=15|L4 - Imaging for Trauma, p.15]] [^16]: Original PDF page 16: [[L4 - Imaging for Trauma.pdf#page=16|L4 - Imaging for Trauma, p.16]] [^17]: Original PDF page 17: [[L4 - Imaging for Trauma.pdf#page=17|L4 - Imaging for Trauma, p.17]] [^18]: Original PDF page 18: [[L4 - Imaging for Trauma.pdf#page=18|L4 - Imaging for Trauma, p.18]] [^19]: Original PDF page 19: [[L4 - Imaging for Trauma.pdf#page=19|L4 - Imaging for Trauma, p.19]] [^20]: Original PDF page 20: [[L4 - Imaging for Trauma.pdf#page=20|L4 - Imaging for Trauma, p.20]] [^21]: Original PDF page 21: [[L4 - Imaging for Trauma.pdf#page=21|L4 - Imaging for Trauma, p.21]] [^22]: Original PDF page 22: [[L4 - Imaging for Trauma.pdf#page=22|L4 - Imaging for Trauma, p.22]] [^23]: Original PDF page 23: [[L4 - Imaging for Trauma.pdf#page=23|L4 - Imaging for Trauma, p.23]] [^24]: Original PDF page 24: [[L4 - Imaging for Trauma.pdf#page=24|L4 - Imaging for Trauma, p.24]] [^25]: Original PDF page 25: [[L4 - Imaging for Trauma.pdf#page=25|L4 - Imaging for Trauma, p.25]] [^26]: Original PDF page 26: [[L4 - Imaging for Trauma.pdf#page=26|L4 - Imaging for Trauma, p.26]] [^27]: Original PDF page 27: [[L4 - Imaging for Trauma.pdf#page=27|L4 - Imaging for Trauma, p.27]] [^28]: Original PDF page 28: [[L4 - Imaging for Trauma.pdf#page=28|L4 - Imaging for Trauma, p.28]] [^29]: Original PDF page 29: [[L4 - Imaging for Trauma.pdf#page=29|L4 - Imaging for Trauma, p.29]] [^30]: Original PDF page 30: [[L4 - Imaging for Trauma.pdf#page=30|L4 - Imaging for Trauma, p.30]] [^31]: Original PDF page 31: [[L4 - Imaging for Trauma.pdf#page=31|L4 - Imaging for Trauma, p.31]] [^32]: Original PDF page 32: [[L4 - Imaging for Trauma.pdf#page=32|L4 - Imaging for Trauma, p.32]] [^33]: Original PDF page 33: [[L4 - Imaging for Trauma.pdf#page=33|L4 - Imaging for Trauma, p.33]] [^34]: Original PDF page 34: [[L4 - Imaging for Trauma.pdf#page=34|L4 - Imaging for Trauma, p.34]] [^35]: Original PDF page 35: [[L4 - Imaging for Trauma.pdf#page=35|L4 - Imaging for Trauma, p.35]] [^36]: Original PDF page 36: [[L4 - Imaging for Trauma.pdf#page=36|L4 - Imaging for Trauma, p.36]] [^37]: Original PDF page 37: [[L4 - Imaging for Trauma.pdf#page=37|L4 - Imaging for Trauma, p.37]] [^38]: Original PDF page 38: [[L4 - Imaging for Trauma.pdf#page=38|L4 - Imaging for Trauma, p.38]] [^39]: Original PDF page 39: [[L4 - Imaging for Trauma.pdf#page=39|L4 - Imaging for Trauma, p.39]] [^40]: Original PDF page 40: [[L4 - Imaging for Trauma.pdf#page=40|L4 - Imaging for Trauma, p.40]] [^41]: Original PDF page 41: [[L4 - Imaging for Trauma.pdf#page=41|L4 - Imaging for Trauma, p.41]] [^42]: Original PDF page 42: [[L4 - Imaging for Trauma.pdf#page=42|L4 - Imaging for Trauma, p.42]] [^43]: Original PDF page 43: [[L4 - Imaging for Trauma.pdf#page=43|L4 - Imaging for Trauma, p.43]] [^44]: Original PDF page 44: [[L4 - Imaging for Trauma.pdf#page=44|L4 - Imaging for Trauma, p.44]] [^45]: Original PDF page 45: [[L4 - Imaging for Trauma.pdf#page=45|L4 - Imaging for Trauma, p.45]] [^46]: Original PDF page 46: [[L4 - Imaging for Trauma.pdf#page=46|L4 - Imaging for Trauma, p.46]] [^47]: Original PDF page 47: [[L4 - Imaging for Trauma.pdf#page=47|L4 - Imaging for Trauma, p.47]] [^48]: Original PDF page 48: [[L4 - Imaging for Trauma.pdf#page=48|L4 - Imaging for Trauma, p.48]] [^49]: Original PDF page 49: [[L4 - Imaging for Trauma.pdf#page=49|L4 - Imaging for Trauma, p.49]]