# Restoration of Endodontically Treated Teeth
Dr. Marrwa Ibrahim
Dr. Marrwa Ibrahim
![]()
3D digital rendering of a mandibular dental arch showing endodontically treated teeth. A central incisor is highlighted with an internal post-and-core restoration visible in white and blue colors, demonstrating the restoration technique for endodontically treated teeth.
![]()
Institutional logo for The University of Western Australia and the Oral Health Centre of Western Australia. This visual element identifies the academic or clinical source of the lecture material.
**Learning Outcomes**
**By the end of this lecture, you should be able to:**
1) Identify drawback and limitation of traditional techniques for post and core fabrication
2) Understand CAD/CAM workflows
3) Compare the digital approach with the traditional technique
4) Apply clinical decision-making
By the end of this lecture, you should be able to:
1. Identify drawback and limitation of traditional techniques for post and core fabrication
2. Understand CAD/CAM workflows
3. Compare the digital approach with the traditional technique
4. Apply clinical decision-making
</img>
**THE UNIVERSITY OF WESTERN AUSTRALIA**
| Oral Health Centre of Western Australia
**Post and core**
**Customized post and cores** | **Prefabricated posts**
**direct technique with a resin pattern** | **indirect technique with the help of elastomeric impressions**
The choice of technique relies on factors such as the tooth's condition, the patient's oral health, and the clinician's proficiency
#### Classification of Post and Core Systems
- **Customized post and cores**
- **Prefabricated posts**
#### Fabrication Techniques
- **Direct technique**: Utilizes a resin pattern.
- **Indirect technique**: Utilizes elastomeric impressions.
The choice of technique relies on factors such as the tooth's condition, the patient's oral health, and the clinician's proficiency.
![]()
Flowchart diagram illustrating the classification of 'Post and core' techniques. The main category splits into two branches: 'Customized post and cores' (left) and 'Prefabricated posts' (right). Under 'Customized post and cores', there are two sub-options connected by curved arrows indicating a relationship or cycle: 'direct technique with a resin pattern' and 'indirect technique with the help of elastomeric impressions'. All elements are enclosed in yellow rectangular boxes.
**The University of Western Australia | Oral Health Centre of Western Australia**
***
# Drawback and Limitations of Traditional techniques for Post a core fabrication
* Shrinkage.
* Distortion.
* Human error.
* Lab variability.
* Multiple visits
* Technique sensitivity
* Material mismatch
Traditional techniques for post and core fabrication are subject to several constraints:
- Shrinkage
- Distortion
- Human error
- Lab variability
- Multiple visits
- Technique sensitivity
- Material mismatch
Digital Dentistry
Is now reshaping the foundations of how restorative procedures are approached in many fields in the dental industry.
- Digital Scanning
- CAD (computer-aided design)
- CAM (computer-aided manufacturing)
Improves reproducibility, reduces operator dependency, improves accuracy, provide consistency through standardized production protocols
Digital dentistry is reshaping the foundations of restorative procedures through three primary components:
- Digital Scanning
- CAD (Computer-Aided Design)
- CAM (Computer-Aided Manufacturing)
#### Benefits of Digital Integration
- Improves reproducibility
- Reduces operator dependency
- Improves accuracy
- Provides consistency through standardized production protocols
**Introduction to CAD/CAM in restoration of endodontically treated teeth:**
Modern dentistry
**CAD** (Digital design) + **CAM** (manufacturing) ➔ Integration
Precision workflow
Digital workflow allows simulation and previsualization of outcomes.
· CAD: software modeling (Exocad, 3Shape)
· CAM: milling/printing systems.
Modern dentistry integrates CAD (digital design) and CAM (manufacturing) to create a precision workflow. This digital workflow allows for the simulation and previsualization of outcomes.
- **CAD**: Software modeling (e.g., Exocad, 3Shape)
- **CAM**: Milling or printing systems
![]()
Clinical photo of a CEREC MC XL dental milling machine. A hand is placing a prepared tooth into the device's scanning or processing chamber. The image visually demonstrates the CAM (Computer-Aided Manufacturing) equipment mentioned in the text.
**CAD/CAM technology encompasses two fundamental approaches:**
1. **Additive manufacturing (3D printing):** brings structures to life by building layer upon layer, each precise deposition contributing to the emergence of intricate forms.
- Efficient with high accuracy
- Minimal waste
Materials used in this technique: resin/metal printing.
Additive manufacturing, or 3D printing, builds structures layer upon layer. Each precise deposition contributes to the emergence of intricate forms.
- Efficient with high accuracy
- Minimal waste
- **Materials used**: Resin or metal printing
# **THE UNIVERSITY OF**
# **WESTERN AUSTRALIA**
# Oral Health Centre
# of Western Australia
**CAD/CAM technology encompasses two fundamental approaches:**
**2. Subtractive manufacturing:** revolves around the art of material removal, sculpting the desired shape by carefully chiseling away.
➢ High strength
➢ Material waste
**Materials used in this technique:**
dense materials (zirconia, Co-Cr)
<div align="right"><img src="image-vue_168.png"/ style="height:56px"></div>
Subtractive manufacturing revolves around material removal, sculpting the desired shape by chiseling away from a solid block.
- High strength
- Material waste
- **Materials used**: Dense materials such as Zirconia or Cobalt-Chromium (Co-Cr)
**Materials in CAD/CAM**
• Zirconia
• Hybrid ceramics
• FRC composites
Material choice affects fracture mode and long-term prognosis.
The choice of material significantly affects the fracture mode and long-term prognosis of the restoration. Common materials include:
- Zirconia
- Hybrid ceramics
- Fiber Reinforced Composite (FRC) materials
The University of Western Australia | Oral Health Centre of Western Australia
**Zirconia**
* High strength
* Aesthetic
* High stiffness risk
* Establishing a strong bond to the acid-resistant zirconia can be challenging
* In case of treatment failure, it may be extremely difficult to retrieve zirconia posts from root canals
**Zirconia:** strong but risk of catastrophic root fracture due to stiffness.
#### Characteristics of Zirconia
- High strength
- Aesthetic
#### Risks and Challenges
- **Stiffness**: High stiffness carries a risk of catastrophic root fracture.
- **Bonding**: Establishing a strong bond to acid-resistant zirconia can be challenging.
- **Retrievability**: In the event of treatment failure, it may be extremely difficult to retrieve zirconia posts from root canals.
![]()
Clinical photo: A white zirconia dental post is shown against a black background. The image illustrates the physical form of the material discussed in the text, which lists properties such as 'High strength', 'Aesthetic', and 'High stiffness risk'. The visual serves to demonstrate the object being analyzed for its bonding challenges and potential for root fracture.
**Hybrid:** The University of Western Australia | Oral Health Centre of Western Australia
**Hybrid Materials:**
Novel materials emerged by blending ceramics with composite resin, resulting in a material that boasts the mechanical properties and color stability of ceramics alongside the elasticity and robustness of resin composites , such as Enamic .
➢ Elastic modulus close to dentin
➢ Better fracture behavior
Hybrid: better stress distribution and repairable failure patterns.
Hybrid materials (such as Enamic) are created by blending ceramics with composite resin. This results in a material that combines the mechanical properties and color stability of ceramics with the elasticity and robustness of resin composites.
- Elastic modulus close to dentin
- Better fracture behavior
- Improved stress distribution
- Repairable failure patterns
## **FRC Materials:**
* Flexible
* Repairable fractures compared to the fracture in case of using zirconia
* excellent aesthetic
* do not require sintering, which reduces manufacturing time and cost.
* FRC: modulus of elasticity closer to dentin, favorable biomechanics properties.
Incorporation of heat-cured denture base acrylics also enhances the marginal strength of
#### Biomechanical Advantages
- Flexible with a modulus of elasticity closer to dentin.
- Favorable biomechanical properties.
- Repairable fractures compared to the catastrophic failures associated with zirconia.
#### Clinical and Manufacturing Benefits
- Excellent aesthetics.
- Does not require sintering, reducing manufacturing time and cost.
- Incorporation of heat-cured denture base acrylics enhances marginal strength.
**The university of**
**WESTERN**
**AUSTRALIA**
**Oral Health Centre**
**of Western Australia**
Techniques for Fabricating CAD/CAM Post and Core
Digital Workflow Overview
Scan → Design → Manufacture
Workflow: intraoral scan → CAD design → CAM production.
The digital workflow for fabricating post and cores follows a standard sequence:
1. **Scan**: Intraoral or impression scanning.
2. **Design**: CAD software modeling.
3. **Manufacture**: CAM production.
![]()
Photo of an intraoral scanning device connected to a laptop. The laptop screen displays a digital scan of teeth in red and white, illustrating the 'Scan' step of the CAD/CAM workflow.
![]()
Screenshot of CAD software interface showing a digital design of a post and core restoration on a molar tooth. The image visualizes the 'Design' step with transparent overlays of the prepared tooth structure and the designed restoration.
![]()
Photo of a dental CAM (Computer-Aided Manufacturing) machine actively printing a ceramic or resin dental restoration. The machine display shows progress at 58%, illustrating the 'Manufacture' step of the workflow.
# 1. Semi-Digital (Indirect) Workflow:
- **Scan** for impression, resin/wax pattern ( scanning the impression requires less chairside time and therefore results in better work efficiency)
- **Virtual design** is created using Exocad or 3Shape software
- **Fabrication** of post and core restoration either by Milling or 3D printing.
- Semi-digital: combines impression/ pattern with digital fabrication.
The semi-digital workflow combines traditional impressions or patterns with digital fabrication:
- **Scan**: Scanning of the impression or a resin/wax pattern. Scanning the impression requires less chairside time and improves efficiency.
- **Virtual Design**: Created using Exocad or 3Shape software.
- **Fabrication**: Post and core produced via milling or 3D printing.
# **THE UNIVERSITY OF WESTERN AUSTRALIA** | **Oral Health Centre of Western Australia**
## **Digital Workflow**
1. Post space preparation
2. Digital impression
3. CAD design
4. CAM fabrication
5. Clinical try-in and cementation
The digital workflow consists of the following steps:
1. Post space preparation
2. Digital impression
3. CAD design
4. CAM fabrication
5. Clinical try-in and cementation
The University of Western Australia | Oral Health Centre of Western Australia
2. Fully Digital (Direct) Workflow:
• **Direct digital impression** of the post space: Using Intraoral scan to scan the prepared post space.
• **Direct CAD design** using Exocad or 3Shape software
• **Fabrication** of post and core restoration either by Milling or 3D printing.
• Fully digital technique is beneficial as it reduces chairside time, simplifies the laboratory procedure for post and core fabrication and eliminates risk of material distortion.
• Depending on efficiency of the intraoral camera system, it might not be indicated for long and narrow post space.
#### Direct Digital Process
- **Direct Digital Impression**: Using an intraoral scanner to scan the prepared post space.
- **Direct CAD Design**: Utilizing Exocad or 3Shape software.
- **Fabrication**: Production via milling or 3D printing.
#### Advantages and Limitations
- **Benefits**: Reduces chairside time, simplifies laboratory procedures, and eliminates the risk of material distortion.
- **Limitations**: Depending on the efficiency of the intraoral camera system, it may not be indicated for long and narrow post spaces.
![]()
Procedure step labeled 'Direct digital impression' showing the process of using an intraoral scan to capture the prepared post space.
![]()
Procedure step labeled 'Direct CAD design' indicating the use of Exocad or 3Shape software for designing the restoration.
![]()
Procedure step labeled 'Fabrication' describing the creation of the post and core restoration via milling or 3D printing methods.
THE UNIVERSITY OF WESTERN AUSTRALIA
Oral Health Centre
of Western Australia
**CAD Design Principles:**
* Customize post length and taper
* Optimize core contour
* Preserve ferrule
#### Design Objectives
- Customize post length and taper
- Optimize core contour
- Preserve ferrule
![]()
Screenshot of the 'Post & Core' module in the 3Shape CAD software. The visual displays a digital model of a tooth with an embedded post and core structure (shown in blue/grey) surrounded by adjacent teeth (gold). The interface includes a sidebar menu on the left and a toolbar at the top.
**THE UNIVERSITY OF WESTERN AUSTRALIA**
Oral Health Centre of Western Australia
**Custom digital design of post and core:**
**Advantages:**
* Precise adaptation
* **Improved marginal fit**
* Reduced laboratory steps
#### Benefits of Custom Digital Design
- Precise adaptation
- Improved marginal fit
- Reduced laboratory steps
The University of Western Australia
Oral Health Centre of Western Australia
**Advantages of Digital Systems**
* Improved precision
* Customization for canal morphology
* Reduced treatment time
* Better lab communication
#### System Advantages
- Improved precision
- Customization for specific canal morphology
- Reduced treatment time
- Enhanced communication with the laboratory
Limitations of Digital Systems
The University of Western Australia | Oral Health Centre of Western Australia
- High cost of equipment
- Learning curve
- Scanner limitations
The implementation of digital systems involves certain constraints:
- High cost of equipment
- Learning curve for the clinician and staff
- Technical limitations of the scanner
![]()
Institutional logo for The University of Western Australia and the Oral Health Centre of Western Australia. This visual element identifies the source or affiliation of the educational material.
**The University of Western Australia** Oral Health Centre of Western Australia
# **CBCT Integration**
* 3D canal morphology
* Accurate post design
* CBCT enables precise anatomical replication of canal.
#### Anatomical Replication
- Provides 3D canal morphology.
- Enables accurate post design.
- CBCT allows for precise anatomical replication of the root canal.
**Key Clinical Take-Home Messages**
* CAD/CAM is future
* Improved outcomes
* Case-based approach
The University of Western Australia | Oral Health Centre of Western Australia
- CAD/CAM represents the future of restorative dentistry.
- Digital workflows lead to improved clinical outcomes.
- A case-based approach is essential for selecting the appropriate technique.
Final scan ready for CAD design
Final scan ready for CAD design
![]()
Screenshot of a CAD software interface displaying a golden-colored 3D digital model of dental anatomy. The image shows the upper and lower jaw structures with detailed teeth morphology. On the left side, there is a vertical sidebar containing UI elements including a U-shaped icon representing the arch view and scanning status text 'Scanning and Saving Finished'. At the bottom of the window, a caption reads 'Final scan ready for CAD design', indicating the workflow stage.
The University of Western Australia
Oral Health Centre
of Western Australia
Michael D Scherer, DMD, MS
www.FastTrackDentalCE.com
3shape
**3Shape TRIOS Post & Core PVS Hybrid Scanning Technique**
3Shape TRIOS Post & Core PVS Hybrid Scanning Technique
![]()
Software interface screenshot demonstrating the '3Shape TRIOS Post & Core PVS Hybrid Scanning Technique'. The main panel displays a 3D digital model of a tooth with a post and core restoration. A green square selection box highlights the specific area being scanned or analyzed. On the left are tool icons for scanning upper/lower arches and analysis functions. On the right is an inset image showing a close-up view of the selected region. Text overlays include the presenter's name (Michael D Scherer, DMD, MS) and website at the bottom.
**References**
1. Ahmed RA, Aseri FA, Alammari AS, Asiri ZS, Al Matir FO, Al Shahrani SS, et al.
**CAD/CAM technologies in post and core restoration of endodontically treated teeth: current evidence, clinical applications, and interdisciplinary perspectives.** *J Clin Pract Med Res.* 2025;1(3):178–189.
2. Rosenstiel SF, Land MF, Fujimoto J.
**Restoration of the endodontically treated tooth.** In: *Contemporary Fixed Prosthodontics*. Philadelphia: Elsevier; 2015. p. 278–280.
3. al-Qarni FD.
**Customized post and cores fabricated with CAD/CAM technology: a literature review.** *Int J Gen Med.* 2022;15:4771–4779.
4. Abhishek G, Chakrabarty A, Kavlekar V, Singh Y, Mahajan S.
**Prosthetic rehabilitation of endodontically treated tooth by using CAD-CAM milled zirconia post and core system: a clinical report.** *Int J Sci Healthc Res.* 2023;8(1):95–97.
5. Lin P, Xu Z, Luo Y, Yin L.
**A digital technique for a prefabricated custom post-and-core restoration.** *J Prosthet Dent.* (Year not specified in extract).
6. Dimitrova M, Vlahova A, Kazakova R.
**Assessment of CAD/CAM fabrication technologies for post and core restorations—A narrative review.** *Medicina.* 2024;60:748.
1. Ahmed RA, Aseri FA, Alammari AS, Asiri ZS, Al Matir FO, Al Shahrani SS, et al. **CAD/CAM technologies in post and core restoration of endodontically treated teeth: current evidence, clinical applications, and interdisciplinary perspectives.** *J Clin Pract Med Res.* 2025;1(3):178–189.
2. Rosenstiel SF, Land MF, Fujimoto J. **Restoration of the endodontically treated tooth.** In: *Contemporary Fixed Prosthodontics*. Philadelphia: Elsevier; 2015. p. 278–280.
3. al-Qarni FD. **Customized post and cores fabricated with CAD/CAM technology: a literature review.** *Int J Gen Med.* 2022;15:4771–4779.
4. Abhishek G, Chakrabarty A, Kavlekar V, Singh Y, Mahajan S. **Prosthetic rehabilitation of endodontically treated tooth by using CAD-CAM milled zirconia post and core system: a clinical report.** *Int J Sci Healthc Res.* 2023;8(1):95–97.
5. Lin P, Xu Z, Luo Y, Yin L. **A digital technique for a prefabricated custom post-and-core restoration.** *J Prosthet Dent.*
6. Dimitrova M, Vlahova A, Kazakova R. **Assessment of CAD/CAM fabrication technologies for post and core restorations—A narrative review.** *Medicina.* 2024;60:748.
The University of Western Australia | Oral Health Centre of Western Australia
**Thank You**
**Thank You**
[^1]: Original PDF page 1: [[L5 Digital Approach to RETT.pdf#page=1|L5 Digital Approach to RETT, p.1]]
[^2]: Original PDF page 2: [[L5 Digital Approach to RETT.pdf#page=2|L5 Digital Approach to RETT, p.2]]
[^3]: Original PDF page 3: [[L5 Digital Approach to RETT.pdf#page=3|L5 Digital Approach to RETT, p.3]]
[^4]: Original PDF page 4: [[L5 Digital Approach to RETT.pdf#page=4|L5 Digital Approach to RETT, p.4]]
[^5]: Original PDF page 5: [[L5 Digital Approach to RETT.pdf#page=5|L5 Digital Approach to RETT, p.5]]
[^6]: Original PDF page 6: [[L5 Digital Approach to RETT.pdf#page=6|L5 Digital Approach to RETT, p.6]]
[^7]: Original PDF page 7: [[L5 Digital Approach to RETT.pdf#page=7|L5 Digital Approach to RETT, p.7]]
[^8]: Original PDF page 8: [[L5 Digital Approach to RETT.pdf#page=8|L5 Digital Approach to RETT, p.8]]
[^9]: Original PDF page 9: [[L5 Digital Approach to RETT.pdf#page=9|L5 Digital Approach to RETT, p.9]]
[^10]: Original PDF page 10: [[L5 Digital Approach to RETT.pdf#page=10|L5 Digital Approach to RETT, p.10]]
[^11]: Original PDF page 11: [[L5 Digital Approach to RETT.pdf#page=11|L5 Digital Approach to RETT, p.11]]
[^12]: Original PDF page 12: [[L5 Digital Approach to RETT.pdf#page=12|L5 Digital Approach to RETT, p.12]]
[^13]: Original PDF page 13: [[L5 Digital Approach to RETT.pdf#page=13|L5 Digital Approach to RETT, p.13]]
[^14]: Original PDF page 14: [[L5 Digital Approach to RETT.pdf#page=14|L5 Digital Approach to RETT, p.14]]
[^15]: Original PDF page 15: [[L5 Digital Approach to RETT.pdf#page=15|L5 Digital Approach to RETT, p.15]]
[^16]: Original PDF page 16: [[L5 Digital Approach to RETT.pdf#page=16|L5 Digital Approach to RETT, p.16]]
[^17]: Original PDF page 17: [[L5 Digital Approach to RETT.pdf#page=17|L5 Digital Approach to RETT, p.17]]
[^18]: Original PDF page 18: [[L5 Digital Approach to RETT.pdf#page=18|L5 Digital Approach to RETT, p.18]]
[^19]: Original PDF page 19: [[L5 Digital Approach to RETT.pdf#page=19|L5 Digital Approach to RETT, p.19]]
[^20]: Original PDF page 20: [[L5 Digital Approach to RETT.pdf#page=20|L5 Digital Approach to RETT, p.20]]
[^21]: Original PDF page 21: [[L5 Digital Approach to RETT.pdf#page=21|L5 Digital Approach to RETT, p.21]]
[^22]: Original PDF page 22: [[L5 Digital Approach to RETT.pdf#page=22|L5 Digital Approach to RETT, p.22]]
[^23]: Original PDF page 23: [[L5 Digital Approach to RETT.pdf#page=23|L5 Digital Approach to RETT, p.23]]
[^24]: Original PDF page 24: [[L5 Digital Approach to RETT.pdf#page=24|L5 Digital Approach to RETT, p.24]]
[^25]: Original PDF page 25: [[L5 Digital Approach to RETT.pdf#page=25|L5 Digital Approach to RETT, p.25]]
[^26]: Original PDF page 26: [[L5 Digital Approach to RETT.pdf#page=26|L5 Digital Approach to RETT, p.26]]
[^27]: Original PDF page 27: [[L5 Digital Approach to RETT.pdf#page=27|L5 Digital Approach to RETT, p.27]]