## Learning Objectives * What is panoramic radiography (PR)? * What are the components of an extra-oral film cassette? * What are intensifying screens? * What is focal trough? * Understanding correct PR techniques * How are artefacts produced? * Understanding PR Anatomy * What are the indications for panoramic imaging?  ### Learning Objectives - What is panoramic radiography (PR)? - What are the components of an extra-oral film cassette? - What are intensifying screens? - What is focal trough? - Understanding correct PR techniques - How are artefacts produced? - Understanding PR Anatomy - What are the indications for panoramic imaging? Illustration of lightbulbs hanging from wires against a dark background. Four white chalk-drawn lightbulbs are unlit at the top. Below them, one yellow lightbulb is illuminated with radiating lines indicating brightness. This visual metaphor relates to the 'Learning Objectives' text on the right, symbolizing ideas or knowledge. Panoramic Imaging • AKA OPG (orthopantomogram) • Tomographic image of maxillofacial structures using a rotating x-ray source & receptor <!-- Image showing X-ray of teeth, skulls jawbone, and labeled diagram of panoramic imaging machine and skull rotation -->   ### Panoramic Imaging - AKA OPG (orthopantomogram) - Tomographic image of maxillofacial structures using a rotating x-ray source & receptor Clinical radiograph (OPG) of the maxillofacial region showing the mandible and maxilla. The image displays multiple teeth with various restorations including crowns and fillings, along with visible dental implants. Schematic diagram illustrating the mechanism of panoramic imaging. It depicts a skull positioned between an X-ray source and receptor, with arrows indicating the direction of rotation for both components around a central axis labeled 'Center of rotation'. Labels include 'Direction of x-ray source around patient', 'Direction of receptor past collimator', and 'Direction of receptor and collimator around patient'.    Clinical photograph showing a patient (woman) undergoing a panoramic dental X-ray scan. She is seated and holding the chin rest of the imaging device, which features a small monitor displaying her facial image. Schematic diagram illustrating the operational sequence of a panoramic X-ray machine. The process begins with 'The film moves inside the cassette carrier', followed by 'Cassette carrier orbits in front of the face'. Next, the 'Tubehead orbits behind the head' to capture images. The sequence concludes at 'Finish'. Arrows indicate the rotational movement of the components around the patient's head outline. A vertical composite radiograph (panoramic view) displaying sequential slices of dental anatomy. The image shows the progression from the upper right quadrant down through the full arch to the lower left quadrant. A large downward-pointing arrow on the far right indicates the direction of the scan or slice progression. A B Cassette front (plastic or thin metal) Sponge rubber Front intensifying screen Emulsion Plastic film base Emulsion Back intensifying screen Sponge rubber Cassette back (thick metal) Fig. 5.21A A standard $18 \times 13$ cm cassette opened up showing the white intensifying screens and the film.   A B - Cassette front (plastic or thin metal) - Sponge rubber - Front intensifying screen - Emulsion - Plastic film base - Emulsion - Back intensifying screen - Sponge rubber - Cassette back (thick metal) Fig. 5.21A A standard 18 × 13 cm cassette opened up showing the white intensifying screens and the film. Clinical photo: A standard 18 x 13 cm cassette opened up, displaying the internal components including the white intensifying screens and the film. Labelled diagram: Cross-sectional view of a cassette showing layers from top to bottom: Cassette front (plastic or thin metal), Sponge rubber, Front intensifying screen, Emulsion, Plastic film base, Emulsion, Back intensifying screen, Sponge rubber, Cassette back (thick metal). **Emulsion layer:** light-sensitive silver halide crystals coated onto both sides of a transparent base material. **Double sided films have _increased optical density_** CASSETTE FRONT FRONT PADDING INTENSIFYING SCREEN DOUBLE-COATED FILM INTENSIFYING SCREEN LEAD FOIL CASSETTE BACK SUPPORT LAYER PHOSPHOR LAYER EMULSION LAYER SUPPORT LAYER EMULSION LAYER PHOSPHOR LAYER SUPPORT LAYER BACK PADDING   #### Emulsion Layer - Light-sensitive silver halide crystals coated onto both sides of a transparent base material. - Double sided films have _increased optical density_. #### Layered Structure - CASSETTE FRONT - FRONT PADDING - INTENSIFYING SCREEN - DOUBLE-COATED FILM - SUPPORT LAYER - EMULSION LAYER - SUPPORT LAYER - EMULSION LAYER - INTENSIFYING SCREEN - LEAD FOIL - CASSETTE BACK - BACK PADDING Clinical photo: A person in a white lab coat is holding an open X-ray cassette. The image shows the interior of the cassette with double-sided film visible between intensifying screens. Labelled diagram: Cross-section of a double-sided film cassette. Labels include CASSSETTE FRONT, FRONT PADDING, INTENSIFYING SCREEN, DOUBLE-COATED FILM (showing EMULSION LAYER and SUPPORT LAYER on both sides), BACK PADDING, LEAD FOIL, CASSETTE BACK, PHOSPHOR LAYER, and SUPPORT LAYER. Focal Trough / Image Layer    Focal Trough / Image Layer Diagram illustrating the 'Focal Trough / Image Layer' concept. It shows a mandible with multiple X-ray beams originating from different angles and converging at a focal point on the dental arch. Labels include 'X-ray source' pointing to one of the beam emitters. Top-down anatomical diagram showing the U-shaped arch of the mandible (lower jaw) inside an outline of a human head. The teeth are depicted as black dots along the curve of the bone. Technical schematic labeled '3D zone'. It depicts a geometric setup involving curved lines representing the mandibular arch, intersecting planes, and measurement indicators labeled 'f', 'd', 'x', and an angle of '8°'. This visualizes the spatial volume or layer being targeted by the imaging technique. **FT** **Fig. 1-10 Position of focal trough (FT) to the jaw for Panorex (left), Orthopantomograph (middle), and Panelipse (right) (based on the work of Lund and Manson-Hing, 1975a).**   **FT** **Fig. 1-10 Position of focal trough (FT) to the jaw for Panorex (left), Orthopantomograph (middle), and Panelipse (right) (based on the work of Lund and Manson-Hing, 1975a).** Diagram showing three schematic outlines of the mandible illustrating the position of the focal trough (FT) for different imaging modalities: Panorex, Orthopantomograph, and Panelipse. Clinical photograph or radiographic view demonstrating the anatomical region covered by an OPG (Orthopantomogram), highlighting the mandible and maxilla. **Note the posterior teeth are still within the focal trough** FT P BEHIND INNER EDGE AT PLANE OUTER EDGE IN FRONT FILM    Note the posterior teeth are still within the focal trough - FT - P - BEHIND - INNER EDGE - AT PLANE - OUTER EDGE - IN FRONT - FILM Diagram illustrating the focal trough (FT) and patient positioning (P). It shows a U-shaped diagram with labels indicating positions relative to the film: 'BEHIND', 'INNER EDGE', 'AT PLANE', 'OUTER EDGE', and 'IN FRONT'. The text 'FILM' is at the bottom. Two black-and-white line drawings of mandibles showing dental arches. The caption notes that posterior teeth remain within the focal trough. Chart demonstrating layer positioning in radiography. Left side shows 'Layer positioning' with a tooth outline and blue line; right side shows 'Result' with multiple teeth aligned on a gray background.  Composite figure demonstrating the effect of object position on radiographic superimposition. The figure is organized into three rows labeled 'In position', 'Behind', and 'In front'. Each row contains a clinical photo (A, C, E) showing a jaw model with an instrument positioned at different distances relative to the X-ray source, and a corresponding radiograph (B, D, F) illustrating how the object's shadow overlaps with tooth roots. A smiley face emoji is present in the right margin next to the top row. # OPG - Patient Positioning **Midsagittal plane: centered** **Occlusal/Frankfort plane:** parallel to floor Focal trough line / canine line Neck straight to avoid excessive overlap cervical spine  - Midsagittal plane: centered - Occlusal/Frankfort plane: parallel to floor - Focal trough line / canine line - Neck straight to avoid excessive overlap cervical spine An instructional diagram illustrating the correct patient positioning for an Orthopantomogram (OPG). The image features a frontal view of a human head and neck. Several anatomical planes are marked with colored lines: a vertical red line indicates the 'Midsagittal plane' which should be centered; a horizontal green line represents the 'Occlusal/Frankfort plane' which must be parallel to the floor; and a faint grey line marks the 'Focal trough line / canine line'. Additional text annotations advise that the 'Neck [should be] straight to avoid excessive overlap cervical spine'. WATCH ➔ https://www.youtube.com/watch?v=YeHp78Dv0fM **Midsagittal** **No jewelry** **No movement (~10-20s; fast modes available when needed)** **Close lips, place and hold tongue against palate** **Frankfort Plane : superior border of the external auditory meatus to the infraorbital rim** **Focal trough line**   - WATCH: https://www.youtube.com/watch?v=YeHp78Dv0fM - Midsagittal - No jewelry - No movement (~10-20s; fast modes available when needed) - Close lips, place and hold tongue against palate - Frankfort Plane: superior border of the external auditory meatus to the infraorbital rim - Focal trough line Clinical procedure image demonstrating cephalometric head positioning. A 3D rendered model of a patient's head is shown inside a bite-block device with laser crosshairs. Labels indicate 'Midsagittal' (vertical center line), 'Frankfort Plane' (horizontal line from ear to eye socket), and 'Focal trough line'. Instructions on the left specify patient requirements: 'No jewelry', 'No movement (~10-20s; fast modes available when needed)', and 'Close lips, place and hold tongue against palate'. Schematic diagram illustrating radiographic layer positioning and result. The image displays three columns labeled 'Film', 'Layer positioning', and 'Result'. It shows a side view of teeth being aligned within a focal trough (blue line) to produce a clear, sharp final radiograph in the result panel.    Clinical photo showing a young male patient positioned at a Planmeca OPG (Orthopantomograph) machine. The image demonstrates the procedure for taking a panoramic dental X-ray. Labels point to the 'beam' source and the 'receptor' plate. The patient is holding a chin rest and has a bite block with a 'Bite peg' inserted between his teeth to ensure proper alignment. Close-up photograph of a transparent acrylic dental component labeled 'Bite grooves'. This object appears to be part of the bite registration mechanism used in radiography to stabilize the patient's jaw position. Technical line drawing illustrating the components of a remote exposure switch system. It labels the 'Holder', the 'Exposure button' connected by a coiled cord, and an indicator panel showing 'EXPOSURE EMISSION' and 'READY PRET' states.    Clinical photo showing a patient using a cephalostat headgear for dental radiography. Labels 'beam' and 'receptor' are positioned above the image to indicate the direction of X-ray emission and placement of the film/sensor. Schematic diagram illustrating cephalometric radiographic technique. It shows an X-ray tube projecting a beam at -8° angulation towards the image receptor positioned behind a profile view of a human head. Diagram demonstrating superimposition errors in dental imaging due to angulation. Panel A shows tooth anatomy with colored circles indicating structures; Panel B shows corresponding projections on the receptor. Arrows labeled L (likely Lingual) and B (likely Buccal) point from anatomical features to their displaced positions on the receptor, illustrating distortion. # Positioning Errors Positioning Errors  Clinical radiograph showing the maxillofacial region with teeth visible. The image includes a caption indicating 'Teeth in front of focal trough', which suggests this is an example illustrating how teeth positioned anterior to the focal trough appear in the radiographic image.  Radiograph showing teeth located behind the focal trough. BEAM Spine not straight No bite peg use (overlapping of teeth)    - BEAM - Spine not straight - No bite peg use (overlapping of teeth) Clinical radiograph (panoramic dental X-ray) showing the maxillary and mandibular arches with multiple restorations. The image is labeled '-8° angulation' indicating the beam angle used for capture. Line drawing comparing two skull profiles to illustrate cephalometric beam alignment. The left panel shows a correct horizontal beam path ('BEAM') aligned with the occlusal plane. The right panel demonstrates incorrect angulation where the beam is tilted relative to the skull. Text-based annotation block summarizing technical errors in the radiographic study: 'Spine not straight' and 'No bite peg use (overlapping of teeth)', providing diagnostic context for the visual data. **Head tilting to the right** - **Incorrect midsagittal** **Chin down** - **Incorrect Frankfort plane** - **"Exaggerated smile"** - **Superiorly positioned hyoid bone** - **Condyles not visible (too high)** **Neck extension** - **Too much spine in the middle**  #### Head tilting to the right - Incorrect midsagittal #### Chin down - Incorrect Frankfort plane - "Exaggerated smile" - Superiorly positioned hyoid bone - Condyles not visible (too high) #### Neck extension - Too much spine in the middle Clinical radiograph (panoramic dental X-ray) showing a patient's dentition and maxillofacial anatomy. The image displays multiple teeth with large radiopaque restorations (fillings). The visual content demonstrates significant positioning errors: the head is tilted to the right, causing an incorrect midsagittal plane; the chin is down, resulting in an incorrect Frankfort plane, an 'exaggerated smile' appearance of the mandible, a superiorly positioned hyoid bone, and condyles that are not visible (too high); and neck extension is evident, showing too much spine in the middle. The X-ray image of a dental scan. **Chin up** - Incorrect Frankfort plane - “Reverse smile” - Condyles not visible **Neck extension** - Too much spine in the middle **Tongue not touching the palate** - Palatoglossal airspace over the maxillary roots  The X-ray image of a dental scan. #### Chin up - Incorrect Frankfort plane - "Reverse smile" - Condyles not visible #### Neck extension - Too much spine in the middle #### Tongue not touching the palate - Palatoglossal airspace over the maxillary roots Dental radiograph (panoramic X-ray) showing the maxilla and mandible with teeth. The image demonstrates specific positioning errors: 'Chin up' causing an incorrect Frankfort plane, a 'Reverse smile' curvature of the occlusal plane, and non-visible condyles. 'Neck extension' is evident as excessive spine shadowing in the midline. 'Tongue not touching the palate' is shown by the presence of palatoglossal airspace over the maxillary roots. Rotated to the right (incorrect midsagittal) - Right-sided posterior teeth are behind the focal trough → horizontal magnification - Asymmetry of the hemimandibles - Opaque appearance of the left maxillary sinus   #### Rotated to the right (incorrect midsagittal) - Right-sided posterior teeth are behind the focal trough → horizontal magnification - Asymmetry of the hemimandibles - Opaque appearance of the left maxillary sinus Clinical panoramic radiograph (orthopantomogram) of the jaws. The image is rotated to the right with an incorrect midsagittal alignment. Key findings include: right-sided posterior teeth positioned behind the focal trough causing horizontal magnification; asymmetry of the hemimandibles; and an opaque appearance of the left maxillary sinus. Schematic diagram illustrating the anatomical orientation of the mandible. Labels 'R' and 'L' indicate Right and Left sides respectively, corresponding to the rotation described in the text. <br> **Rotated to R**   **Rotated to R** Clinical photo: Panoramic dental radiograph showing the maxilla and mandible with multiple teeth. The image includes visible roots, crowns, and surrounding bone structures. A black bar is present at the top center of the image, likely obscuring patient identification information. Text label indicating that the radiographic image has been rotated to the right (R) for orientation purposes.  Clinical radiograph showing a panoramic view of the mandible and maxilla. The image demonstrates dental structures including teeth roots and alveolar bone. A prominent bright artifact (likely from metal or equipment) is visible in the central region, labeled with handwritten text 'L 759'. The caption 'Shoulder hit' indicates potential trauma or positional artifact affecting the shoulder area during imaging.  Radiograph of the mandible and maxilla showing dental structures. The image exhibits horizontal blurring and ghosting artifacts consistent with patient movement during exposure. Visible teeth include molars with radiopaque restorations (fillings) in both arches. The caption indicates horizontal motion causing deletion and doubling effects.  Clinical radiograph showing the maxillofacial region with multiple teeth. The image displays a dental anomaly labeled as 'Doubling of 74 & 34', indicating supernumerary or duplicated teeth in the mandibular posterior regions (likely second molars). The radiographic features include overlapping tooth structures and abnormal root formations consistent with dental doubling. # Real Images, Ghost Images & Double Images ### Real Images, Ghost Images & Double Images Real Image on OPG * Object is **between centre of rotation** and receptor * Sharper if closer to focal trough Ear ring 0 X ray tube L   #### Real Image on OPG - Object is **between centre of rotation** and receptor - Sharper if closer to focal trough Ear ring 0 X ray tube L Diagram showing the anatomical alignment for an Orthopantomogram (OPG). It depicts a lateral view of the mandible and cervical spine. Dotted lines trace the focal trough path along the dental arches to indicate where sharp images are captured. Real OPG radiograph displaying the patient's dentition and maxilla/mandible. Red circles highlight two distinct objects on either side of the jaw: a solid white circular object on the left and a striped circular object on the right, demonstrating how objects between the center of rotation and receptor appear in the image. Ghost Image on OPG • Object between x-ray source and centre of rotation • Usually outside of focal trough: appears blurred and magnified • Appears on opposite side of image (L↔R) and higher on the image (due to **upward beam**) than their anatomical location • Mandibular ramus, hyoid bone, cervical spine, earrings, etc.    #### Ghost Image on OPG - Object between x-ray source and centre of rotation - Usually outside of focal trough: appears blurred and magnified - Appears on opposite side of image (L↔R) and higher on the image (due to **upward beam**) than their anatomical location - Mandibular ramus, hyoid bone, cervical spine, earrings, etc. Anatomical diagram illustrating the concept of a ghost image on an OPG. It shows a top-down view of the mandible and cervical spine with dotted lines indicating the path of the x-ray beam passing through an object (e.g., ear ring) located between the source and the center of rotation. Schematic diagram demonstrating the geometry of ghost image formation. It depicts the 'Image receptor', 'Ear ring' positioned at the center of rotation, and green arrows representing the x-ray beam paths causing the object to appear magnified and displaced on the opposite side. Clinical radiograph (OPG) showing actual ghost images of earrings (circled in red). Red arrows point from the anatomical location of the earrings to their displaced positions on the opposite side of the image, visually confirming the phenomenon described in the text.  Clinical radiograph (panoramic X-ray) of the mandible showing bilateral dental arches with multiple teeth. The image includes anatomical landmarks such as the mandibular rami and angle regions. A marker labeled 'R' is visible in the lower-left corner indicating the right side of the patient. **Double Image on OPG** • Object is posterior to centre of rotation (**the red diamond area**) and intercepted by beam twice • Structures in the centre eg. Hyoid bone, epiglottis, cervical spine, palate • Double images are **mirror images**, appearing on the **same location** but opposite sides Starting angle of panoramic exposure End angle of panoramic exposure Trajectory of center of rotation   #### Double Image on OPG - Object is posterior to centre of rotation (**the red diamond area**) and intercepted by beam twice - Structures in the centre eg. Hyoid bone, epiglottis, cervical spine, palate - Double images are **mirror images**, appearing on the **same location** but opposite sides Starting angle of panoramic exposure End angle of panoramic exposure Trajectory of center of rotation Schematic diagram illustrating the concept of double images on an OPG. It shows a skeletal view of the maxilla and mandible with a central green diamond shape representing the area where objects are intercepted by the X-ray beam twice. Clinical radiograph (OPG) demonstrating the appearance of double images as described in the text. The image shows the dentition and jaw structures with artifacts consistent with mirror imaging of posterior structures like the hyoid bone or cervical spine.  Diagram showing three zones of a dental radiograph: Real Image Zone (left), Double Image Zone (center), and Ghost Image Zone (right). Each zone is illustrated with a jawbone structure and shaded areas indicating the extent of the image artifact. # OPG artefacts - Incorrect patient positioning - Chin down - Chin up - Head tilting - Head rotation - Movement - Horizontal (following the beam or opposite to the beam direction) - Vertical - Swallowing - Soft tissue position - Tongue to the palate - Lips closed - Focal trough position - Head in front of the focal trough - Head behind the focal trough - Neck extension - Collision with shoulder - Ghost images - Foreign materials eg. Earrings, necklace, denture left in situ, etc. #### OPG artefacts - Incorrect patient positioning - Chin down - Chin up - Head tilting - Head rotation - Movement - Horizontal (following the beam or opposite to the beam direction) - Vertical - Swallowing - Soft tissue position - Tongue to the palate - Lips closed - Focal trough position - Head in front of the focal trough - Head behind the focal trough - Neck extension - Collision with shoulder - Ghost images - Foreign materials eg. Earrings, necklace, denture left in situ, etc. | Error | Appearance on Image | Correction | | :--- | :--- | :--- | | **Ghost images** | Ghost image resembles real image | Have patient remove all radiodense objects before exposure | | | Projected on opposite side of film and is higher | | | **Lead apron artifact** | Radiopaque, cone-shaped artifact in center of image | Use lead apron without thyroid collar | | **Patient lips not closed** | Dark radiolucent shadow around anterior teeth | Remind patient to close lips around bite block | | **Patient chin too high** | Condyles may not be visible | Keep Frankfort plane parallel with floor | | | Maxillary incisors appear blurred and magnified. | | | | Reverse smile line (frown) or flat occlusal plane | | | **Patient chin too low** | Exaggerated smile line (Joker) | Keep Frankfort plane parallel with floor | | | Condyles higher on image | | | | Mandibular incisors appear blurred; roots appear short | | | **Patient too far forward** <br>(in front of focal trough) | Anterior teeth appear narrow | Make sure patient's teeth are in bite block notches & Focal trough line is at the tip of the Mx canines | | | Spine is visible on film | | | **Patient too far back** <br>(posterior to focal trough) | Anterior teeth appear magnified | Make sure patient's teeth are in bite block notches & Focal trough line is at the tip of the Mx canines | | | Ramus isn't entirely visible | | | **Patient head not centered** <br>(Head rotation to right / left) | Ramus and posterior teeth appear unequally magnified | Keep midsagittal plane perpendicular to floor & ensure indicating light is located at center of patient’s nose | | | Side farthest from receptor appears magnified | | | | Side closest to receptor appears smaller | | | | Example: Patient turned to right will produce image with magnification on right side and overlapping of contacts | | | **Head Tilt** | Asymmetry of the face on OPG. Eg. Head tilt to the right -> The right side of the face is more inferiorly positioned than the LHS | Ensure the patient’s midline & the frankfort plane are perpendicular to each other | | **Tongue not touching the palate** | Glossopalatal airspace is superimposed over the Mx tooth roots. | Make sure the patient's tongue is touching the palate during the scan (without swallowing) | | **Patient spine isn't straight** / <br>**neck extension** | Cervical spine (ghost image) appears as linear radiopacity in center of image | Have patient stand as tall as possible. Seat patient if necessary. | | **Swallowing** | Soft palate is lifted to the nasopharynx (blocking the airflow) + Hyoid bone is lifted | Make sure the patient does not swallow during the scan |  | Error | Appearance on Image | Correction | | :--- | :--- | :--- | | **Ghost images** | Ghost image resembles real image | Have patient remove all radiodense objects before exposure | | | Projected on opposite side of film and is higher | | | **Lead apron artifact** | Radiopaque, cone-shaped artifact in center of image | Use lead apron without thyroid collar | | **Patient lips not closed** | Dark radiolucent shadow around anterior teeth | Remind patient to close lips around bite block | | **Patient chin too high** | Condyles may not be visible | Keep Frankfort plane parallel with floor | | | Maxillary incisors appear blurred and magnified. | | | | Reverse smile line (frown) or flat occlusal plane | | | **Patient chin too low** | Exaggerated smile line (Joker) | Keep Frankfort plane parallel with floor | | | Condyles higher on image | | | | Mandibular incisors appear blurred; roots appear short | | | **Patient too far forward** <br>(in front of focal trough) | Anterior teeth appear narrow | Make sure patient's teeth are in bite block notches & Focal trough line is at the tip of the Mx canines | | | Spine is visible on film | | | **Patient too far back** <br>(posterior to focal trough) | Anterior teeth appear magnified | Make sure patient's teeth are in bite block notches & Focal trough line is at the tip of the Mx canines | | | Ramus isn't entirely visible | | | **Patient head not centered** <br>(Head rotation to right / left) | Ramus and posterior teeth appear unequally magnified | Keep midsagittal plane perpendicular to floor & ensure indicating light is located at center of patient’s nose | | | Side farthest from receptor appears magnified | | | | Side closest to receptor appears smaller | | | | Example: Patient turned to right will produce image with magnification on right side and overlapping of contacts | | | **Head Tilt** | Asymmetry of the face on OPG. Eg. Head tilt to the right -> The right side of the face is more inferiorly positioned than the LHS | Ensure the patient’s midline & the frankfort plane are perpendicular to each other | | **Tongue not touching the palate** | Glossopalatal airspace is superimposed over the Mx tooth roots. | Make sure the patient's tongue is touching the palate during the scan (without swallowing) | | **Patient spine isn't straight** / <br>**neck extension** | Cervical spine (ghost image) appears as linear radiopacity in center of image | Have patient stand as tall as possible. Seat patient if necessary. | | **Swallowing** | Soft palate is lifted to the nasopharynx (blocking the airflow) + Hyoid bone is lifted | Make sure the patient does not swallow during the scan | A table summarizing errors in dental radiography (specifically OPGs), their appearance on the image, and corrections. Columns are 'Error', 'Appearance on Image', and 'Correction'. Rows cover issues such as Ghost images, Lead apron artifact, Patient lips not closed, Patient chin too high/low, Patient too far forward/back, Patient head not centered, Head Tilt, Tongue not touching the palate, Patient spine isn't straight, and Swallowing. OPG Anatomy OPG Anatomy OPG Anatomy Exercise - Teeth (count teeth first) - Hard palate & Soft palate - Maxilla - Incisive canal - Intermaxillary suture - Maxillary sinuses - Draw Floor, Anterior and Posterior walls - Innominate line (zygomatic process) - Mandible - Angle, ramus, body, coronoid process, condylar neck, condylar head, pterygoid fovea, sigmoid notch - External oblique ridge - Submandibular fossa - Mandibular canal & Mental foramen - Zygomatic arch - Zygomatico-zygomatic suture - Zygomatic process of temporal bone - Articular eminence - Pterygoid plates - Pterygomaxillary fissure - Orbital rims - Infraorbital canal & foramen - Nose - Nasal cavity, septum, turbinate (conchae) - Soft tissue - Anterior nasal spine - Hyoid bone - Epiglottis - Cervical spine - C1, C2, C3, C4 - Atlanto-axial joint space - Styloid process - Mastoid process - Ears - External auditory meati - Soft tissue - Tongue (dorsal border) - Tonsillar tissues (if visible) - Facial soft tissue creases – e.g. naso-labial folds (if visible) - Posterior pharyngeal wall - Airspaces - Palatoglossal airspace (when tongue is not up) - Nasopharynx and oropharynx - Teeth (count teeth first) - Hard palate & Soft palate - Maxilla - Incisive canal - Intermaxillary suture - Maxillary sinuses - Draw Floor, Anterior and Posterior walls - Innominate line (zygomatic process) - Mandible - Angle, ramus, body, coronoid process, condylar neck, condylar head, pterygoid fovea, sigmoid notch - External oblique ridge - Submandibular fossa - Mandibular canal & Mental foramen - Zygomatic arch - Zygomatico-zygomatic suture - Zygomatic process of temporal bone - Articular eminence - Pterygoid plates - Pterygomaxillary fissure - Orbital rims - Infraorbital canal & foramen - Nose - Nasal cavity, septum, turbinate (conchae) - Soft tissue - Anterior nasal spine - Hyoid bone - Epiglottis - Cervical spine - C1, C2, C3, C4 - Atlanto-axial joint space - Styloid process - Mastoid process - Ears - External auditory meati - Soft tissue - Tongue (dorsal border) - Tonsillar tissues (if visible) - Facial soft tissue creases – e.g. naso-labial folds (if visible) - Posterior pharyngeal wall - Airspaces - Palatoglossal airspace (when tongue is not up) - Nasopharynx and oropharynx  A panoramic dental radiograph showing the complete dentition with teeth numbered according to the Universal Numbering System. The image displays both maxillary and mandibular arches, including primary (deciduous) and permanent teeth. Visible labels include: upper left quadrant teeth (18, 17, 16, 15, 14, 13), upper right quadrant teeth (28, 27, 26, 25, 24, 23), lower left quadrant teeth (48, 47, 46, 45, 44, 43, 42, 41), and lower right quadrant teeth (38, 37, 36, 35, 34, 33, 32, 31). Additionally, some primary teeth are labeled with numbers in the 50s (e.g., 53, 55, 85). In the top right corner, there is a book cover titled 'Atlas of Oral and Maxillofacial Radiology' by Bernard Koong, published by Wiley Blackwell. Practice OPG #1 **Find retained deciduous teeth**  Practice OPG #1 **Find retained deciduous teeth** Clinical radiograph (OPG) of the mandible and maxilla showing the dentition. The image includes the text 'Practice OPG #1' at the top left and '*Find retained deciduous teeth*' as an instruction at the top center.  Radiograph showing the dental arches and surrounding bone structure.  Clinical radiograph: Panoramic dental X-ray (OPG) showing the maxillary and mandibular arches with visible teeth, alveolar bone, and surrounding craniofacial structures. **Note the double image of palate, hyoid & spine** 1. Pterygomaxillary fissure 2. Posterior border of maxilla 3. Maxillary tuberosity 4. Maxillary sinus 5. Floor of the maxillary sinus 6. Medial border of maxillary sinus/ lateral border of the nasal cavity 7. Floor of the orbit 8. Infraorbital canal 9. Nasal cavity 10. Nasal septum 11. Floor of the nasal cavity 12. Anterior nasal spine 13. Incisive foramen 14. Hard palate/floor of the nasal cavity 15. Zygomatic process of the maxilla 16. Zygomatic arch 17. Articular eminence 18. External auditory meatus 19. Styloid process 20. Mandibular condyle 21. Sigmoid notch 22. Coronoid process 23. Posterior border of ramus 24. Angle of mandible 25. Hyoid bone 26. Inferior border of mandible 27. Mental foramen 28. Mandibular canal 29. Cervical vertebrae 30. Epiglottis    **Note the double image of palate, hyoid & spine** 1. Pterygomaxillary fissure 2. Posterior border of maxilla 3. Maxillary tuberosity 4. Maxillary sinus 5. Floor of the maxillary sinus 6. Medial border of maxillary sinus/ lateral border of the nasal cavity 7. Floor of the orbit 8. Infraorbital canal 9. Nasal cavity 10. Nasal septum 11. Floor of the nasal cavity 12. Anterior nasal spine 13. Incisive foramen 14. Hard palate/floor of the nasal cavity 15. Zygomatic process of the maxilla 16. Zygomatic arch 17. Articular eminence 18. External auditory meatus 19. Styloid process 20. Mandibular condyle 21. Sigmoid notch 22. Coronoid process 23. Posterior border of ramus 24. Angle of mandible 25. Hyoid bone 26. Inferior border of mandible 27. Mental foramen 28. Mandibular canal 29. Cervical vertebrae 30. Epiglottis Clinical radiograph (panoramic X-ray) showing the maxilla and mandible with dentition. The image is labeled 'A' on the left and 'L' on the right. Anatomical diagram of the skull base and facial skeleton, labeled 'B' and 'L'. It includes callouts pointing to specific anatomical landmarks such as the pterygomaxillary fissure, maxillary sinus, nasal cavity, hard palate, zygomatic arch, mandibular condyle, hyoid bone, and cervical vertebrae. Legend table listing numbered anatomical structures corresponding to the diagram above. Includes entries for: Pterygomaxillary fissure, Posterior border of maxilla, Maxillary tuberosity, Maxillary sinus, Floor of the maxillary sinus, Medial border of maxillary sinus/lateral border of the nasal cavity, Floor of the orbit, Infraorbital canal, Nasal cavity, Nasal septum, Floor of the nasal cavity, Anterior nasal spine, Incisive foramen, Hard palate/floor of the nasal cavity, Zygomatic process of the maxilla, Zygomatic arch, Articular eminence, External auditory meatus, Styloid process, Mandibular condyle, Sigmoid notch, Coronoid process, Posterior border of ramus, Angle of mandible, Hyoid bone, Inferior border of mandible, Mental foramen, Mandibular canal, Cervical vertebrae, and Epiglottis.  Lateral cephalometric radiograph of a skull. The image is annotated with red lines and text labels identifying various anatomical structures. Visible labeled regions include: Inferior turbinate, Nasal septum, Hard palate, Zygomatic arch, Articular tubercle, External auditory meatus, Superior surface of soft palate, Mastoid process, Styloid process, Lobule of external ear, Soft palate, Glossopalatal air space, Epiglottis, Lingual tonsil, Epiglottic vallecula, Greater cornu of hyoid bone, Antegonial notch, Body of hyoid bone, Mental foramen, Mandibular symphysis, Anterior loop of the mandibular canal, and Mental tubercle. Dental X-ray showing mandible anatomy. 1, Mandibular condyle. 2, Neck of mandibular condyle. 3, Coronoid process of mandible. 4, Ghost image, posterior aspect of inferior border of left side of mandible. 5, Inferior alveolar (mandibular) canal. 6, Inferior border of mandible. 7, Superimposed shadow of cervical vertebrae. 8, Mental foramen. 9, Submandibular fossa 10, Mandibular angle. 11, External oblique ridge. 12, Sigmoid notch.  Dental X-ray showing mandible anatomy. 1. Mandibular condyle. 2. Neck of mandibular condyle. 3. Coronoid process of mandible. 4. Ghost image, posterior aspect of inferior border of left side of mandible. 5. Inferior alveolar (mandibular) canal. 6. Inferior border of mandible. 7. Superimposed shadow of cervical vertebrae. 8. Mental foramen. 9. Submandibular fossa 10. Mandibular angle. 11. External oblique ridge. 12. Sigmoid notch. Clinical radiograph (panoramic dental X-ray) of the mandible. The image displays labeled anatomical landmarks with corresponding arrows: 1 Mandibular condyle, 2 Neck of mandibular condyle, 3 Coronoid process of mandible, 4 Ghost image posterior aspect inferior border left side mandible, 5 Inferior alveolar canal, 6 Inferior border of mandible, 7 Superimposed shadow of cervical vertebrae, 8 Mental foramen, 9 Submandibular fossa, 10 Mandibular angle, 11 External oblique ridge, and 12 Sigmoid notch. 1, Articular eminence of temporal bone. 2, Zygomatic arch. 3, Zygomatic process of maxilla (innominate line). 4, Pterygomaxillary fissure. 5, Floor of orbit. 6, inferior turbinate / concha. 7, Nasal septum. 8, Anterior nasal spine. 9, Floor of maxillary sinus. 10, Maxillary left third molar (developing). 11, Ear lobe. 12, Cervical vertebral body. ---  1. Articular eminence of temporal bone. 2. Zygomatic arch. 3. Zygomatic process of maxilla (innominate line). 4. Pterygomaxillary fissure. 5. Floor of orbit. 6. inferior turbinate / concha. 7. Nasal septum. 8. Anterior nasal spine. 9. Floor of maxillary sinus. 10. Maxillary left third molar (developing). 11. Ear lobe. 12. Cervical vertebral body. Clinical radiograph (orthopantomogram) of the maxillofacial region showing labeled anatomical landmarks. Visible structures include: Articular eminence of temporal bone (1), Zygomatic arch (2), Zygomatic process of maxilla (innominate line) (3), Pterygomaxillary fissure (4), Floor of orbit (5), Inferior turbinate/concha (6), Nasal septum (7), Anterior nasal spine (8), Floor of maxillary sinus (9), Maxillary left third molar (developing) (10), Ear lobe (11), and Cervical vertebral body (12). The image includes an on-page legend listing these numbered labels.  Annotated medical diagram showing the anatomy of the maxillofacial region. The image includes labels pointing to: Middle turbinate, Nasal septum, Inferior turbinate, Tip of nose, Soft palate, Ear lobe, and Tongue. The nasal cavity structures are highlighted in green, the soft palate in orange/yellow, and the oral cavity/tongue area in purple.  Medical diagram showing a cross-section of the human head and neck with labeled airway structures. Labels include: Nasal airway (pointing to nasal cavity), Nasopharynx (upper pharyngeal region), Oral airway (mouth/throat area), Velopharynx (posterior to oral cavity), and Oropharynx (lower throat region). The image includes anatomical details such as teeth and jaw structure. **_OPGs are NOT accurate for caries assessment_** “General dental screening” * Impacted third molars * Periodontal screening (periodontal bone loss) * Mixed dentition & Eruption pattern of permanent teeth * Orthodontics * Crowding, impacted canines, etc. * Dental anomalies * Jaw Pathology * Inflammatory lesions, odontogenic tumours & cysts, etc. * Trauma (esp. mandibular fracture) * **TM Joints** (not accurate ) **_OPGs are NOT accurate for caries assessment_** **Clinical Indications:** - General dental screening: - Impacted third molars - Periodontal screening (periodontal bone loss) - Mixed dentition & Eruption pattern of permanent teeth - Orthodontics: - Crowding, impacted canines, etc. - Dental anomalies - Jaw Pathology: - Inflammatory lesions, odontogenic tumours & cysts, etc. - Trauma (esp. mandibular fracture) - **TM Joints** (not accurate) # Further Reading **Essentials of dental radiography and radiology** 5th edition by Whaites, Eric; Drage, Nicholas Churchill Livingstone 2013 **Pocket atlas of dental radiology** by Pasler, Friedrich A; Visser, Heiko Flexibook, 2007 **Oral radiology: principles and interpretation** 7th edition by White, Stuart C; Pharoah, M. J Permalink 2014 - 8th edition available now [^1]: Original PDF page 1: [[L8 Panoramic Radiography.pdf#page=1|L8 Panoramic Radiography, p.1]] [^2]: Original PDF page 2: [[L8 Panoramic Radiography.pdf#page=2|L8 Panoramic Radiography, p.2]] [^3]: Original PDF page 3: [[L8 Panoramic Radiography.pdf#page=3|L8 Panoramic Radiography, p.3]] [^4]: Original PDF page 4: [[L8 Panoramic Radiography.pdf#page=4|L8 Panoramic Radiography, p.4]] [^5]: Original PDF page 5: [[L8 Panoramic Radiography.pdf#page=5|L8 Panoramic Radiography, p.5]] [^6]: Original PDF page 6: [[L8 Panoramic Radiography.pdf#page=6|L8 Panoramic Radiography, p.6]] [^7]: Original PDF page 7: [[L8 Panoramic Radiography.pdf#page=7|L8 Panoramic Radiography, p.7]] [^8]: Original PDF page 8: [[L8 Panoramic Radiography.pdf#page=8|L8 Panoramic Radiography, p.8]] [^9]: Original PDF page 9: [[L8 Panoramic Radiography.pdf#page=9|L8 Panoramic Radiography, p.9]] [^10]: Original PDF page 10: [[L8 Panoramic Radiography.pdf#page=10|L8 Panoramic Radiography, p.10]] [^11]: Original PDF page 11: [[L8 Panoramic Radiography.pdf#page=11|L8 Panoramic Radiography, p.11]] [^12]: Original PDF page 12: [[L8 Panoramic Radiography.pdf#page=12|L8 Panoramic Radiography, p.12]] [^13]: Original PDF page 13: [[L8 Panoramic Radiography.pdf#page=13|L8 Panoramic Radiography, p.13]] [^14]: Original PDF page 14: [[L8 Panoramic Radiography.pdf#page=14|L8 Panoramic Radiography, p.14]] [^15]: Original PDF page 15: [[L8 Panoramic Radiography.pdf#page=15|L8 Panoramic Radiography, p.15]] [^16]: Original PDF page 16: [[L8 Panoramic Radiography.pdf#page=16|L8 Panoramic Radiography, p.16]] [^17]: Original PDF page 17: [[L8 Panoramic Radiography.pdf#page=17|L8 Panoramic Radiography, p.17]] [^18]: Original PDF page 18: [[L8 Panoramic Radiography.pdf#page=18|L8 Panoramic Radiography, p.18]] [^19]: Original PDF page 19: [[L8 Panoramic Radiography.pdf#page=19|L8 Panoramic Radiography, p.19]] [^20]: Original PDF page 20: [[L8 Panoramic Radiography.pdf#page=20|L8 Panoramic Radiography, p.20]] [^21]: Original PDF page 21: [[L8 Panoramic Radiography.pdf#page=21|L8 Panoramic Radiography, p.21]] [^22]: Original PDF page 22: [[L8 Panoramic Radiography.pdf#page=22|L8 Panoramic Radiography, p.22]] [^23]: Original PDF page 23: [[L8 Panoramic Radiography.pdf#page=23|L8 Panoramic Radiography, p.23]] [^24]: Original PDF page 24: [[L8 Panoramic Radiography.pdf#page=24|L8 Panoramic Radiography, p.24]] [^25]: Original PDF page 25: [[L8 Panoramic Radiography.pdf#page=25|L8 Panoramic Radiography, p.25]] [^26]: Original PDF page 26: [[L8 Panoramic Radiography.pdf#page=26|L8 Panoramic Radiography, p.26]] [^27]: Original PDF page 27: [[L8 Panoramic Radiography.pdf#page=27|L8 Panoramic Radiography, p.27]] [^28]: Original PDF page 28: [[L8 Panoramic Radiography.pdf#page=28|L8 Panoramic Radiography, p.28]] [^29]: Original PDF page 29: [[L8 Panoramic Radiography.pdf#page=29|L8 Panoramic Radiography, p.29]] [^30]: Original PDF page 30: [[L8 Panoramic Radiography.pdf#page=30|L8 Panoramic Radiography, p.30]] [^31]: Original PDF page 31: [[L8 Panoramic Radiography.pdf#page=31|L8 Panoramic Radiography, p.31]] [^32]: Original PDF page 32: [[L8 Panoramic Radiography.pdf#page=32|L8 Panoramic Radiography, p.32]] [^33]: Original PDF page 33: [[L8 Panoramic Radiography.pdf#page=33|L8 Panoramic Radiography, p.33]] [^34]: Original PDF page 34: [[L8 Panoramic Radiography.pdf#page=34|L8 Panoramic Radiography, p.34]] [^35]: Original PDF page 35: [[L8 Panoramic Radiography.pdf#page=35|L8 Panoramic Radiography, p.35]] [^36]: Original PDF page 36: [[L8 Panoramic Radiography.pdf#page=36|L8 Panoramic Radiography, p.36]] [^37]: Original PDF page 37: [[L8 Panoramic Radiography.pdf#page=37|L8 Panoramic Radiography, p.37]] [^38]: Original PDF page 38: [[L8 Panoramic Radiography.pdf#page=38|L8 Panoramic Radiography, p.38]] [^39]: Original PDF page 39: [[L8 Panoramic Radiography.pdf#page=39|L8 Panoramic Radiography, p.39]] [^40]: Original PDF page 40: [[L8 Panoramic Radiography.pdf#page=40|L8 Panoramic Radiography, p.40]] [^41]: Original PDF page 41: [[L8 Panoramic Radiography.pdf#page=41|L8 Panoramic Radiography, p.41]] [^42]: Original PDF page 42: [[L8 Panoramic Radiography.pdf#page=42|L8 Panoramic Radiography, p.42]] [^43]: Original PDF page 43: [[L8 Panoramic Radiography.pdf#page=43|L8 Panoramic Radiography, p.43]] [^44]: Original PDF page 44: [[L8 Panoramic Radiography.pdf#page=44|L8 Panoramic Radiography, p.44]] [^45]: Original PDF page 45: [[L8 Panoramic Radiography.pdf#page=45|L8 Panoramic Radiography, p.45]] [^46]: Original PDF page 46: [[L8 Panoramic Radiography.pdf#page=46|L8 Panoramic Radiography, p.46]]