Root Canal Treated Posterior TeethNCT07836920
Conservative Versus Conventional Restorative Approach for Endodontically Treated Posterior Teeth
A study testing Fiber reinforced composite core and an overlay and Fiber post with composite core build up and lithium disilicate full coverage crown in people with Root Canal Treated Posterior Teeth and Endodontically-Treated Teeth, run by Moataz Mostafa Anwar at 1 site in Egypt.
Trial summary
This study compares two methods of restoring posterior teeth after root canal treatment. Traditionally, dentists use fiber posts and full coverage crowns, but this requires removing more tooth structure, which can weaken teeth further. Read more about this study
- Who is it for?
- Ages 20 to 50 years
- Conditions the study is for
- Root Canal Treated Posterior Teeth, Endodontically-Treated Teeth
- What is being tested?
- Fiber reinforced composite core and an overlay and Fiber post with composite core build up and lithium disilicate full coverage crown
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 50 participants
- Where
- 1 siteEgypt
- Study dates
- 20 Sep 2025to Jun 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 20 to 50 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Patients 20-50 years of age
- Root canal treated posterior teeth
- Good C/R ratio
- Good quality root canal treatment (adequate working length, absence of post operative complications or pain and adequate follow up period)
- Presence of adequate labial and palatal wall thickness
- Natural antagonist teeth
- Natural adjacent teeth
Who cannot join
- Improper root canal treatment
- Post operative complications.
- Cracked teeth
- Parafunctional habits (bruxism)
- Wear pattern
- Pregnancy for females
Show all 9Show fewer
- Opposing prosthetics
- Presence of periodontal disease
- Severely destructed posterior teeth
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Egypt1 site, 1 recruiting
- Recruiting
Faculty of Dentistry, Cairo University
Cairo, Manial
Reham S Elbasty, MSC, PhD, +201207169671, reham.elbasty@dentistry.cu.edu.eg
About this study
Official title: Clinical Evaluation of the Conservative Versus Conventional Restorative Approach for Endodontically Treated Posterior Teeth: A Randomized Clinical Trial
This study compares two methods of restoring posterior teeth after root canal treatment. Traditionally, dentists use fiber posts and full coverage crowns, but this requires removing more tooth structure, which can weaken teeth further. A newer, more conservative option is the overlay, which preserves more of the natural tooth. While overlays appear promising, evidence is still limited, particularly for posterior teeth.
The trial, conducted at Cairo University, will involve fifty patients aged 20-50 with properly root canal treated posterior teeth. Participants will be randomly divided into two groups: one receiving a fiber-reinforced composite with a lithium disilicate overlay (conservative method), and the other receiving a fiber post, composite core, and full coverage lithium disilicate crown (conventional method).
The primary outcome will be tooth integrity after six months, evaluated with standardized criteria. Secondary outcomes include margin quality, discoloration, secondary decay, color matching, and patient satisfaction. Patients will be blinded to the treatment they receive, and data will be analyzed using appropriate statistical methods.
Read the detailed description
This research protocol explores two different ways of restoring posterior teeth after root canal treatment. Teeth that have had root canal treatment often become weaker because part of their natural structure is removed, and the dentin itself becomes more fragile. As a result, these teeth are more likely to break. Dentists have usually treated this problem by placing a fiber post inside the root canal and then covering the tooth with a full coverage crown. This method has worked well, but it involves drilling inside the root canal, which can make the tooth weaker on the long run.
With advances in modern dentistry, new techniques aim to be more conservative; they try to save as much of the natural tooth as possible. One of these approaches is the overlay, a type of partial coverage restoration that seats on top of the tooth but does not require as much removal of healthy structure as a full coverage crown. Recent studies suggest that overlays can perform just as well as crowns, but there is still not enough strong clinical evidence to confirm this for all cases, especially for posterior teeth that face heavy biting forces. This trial will help fill that gap in the literature.
The study will take place at the Faculty of Dentistry, Cairo University, and will include fifty patients aged between 20 and 50 years. All patients must have had root canal treatment on a restorable posterior tooth. Those with poorly treated canals, cracked teeth, gum disease, or bruxism will not be included. Patients who join the trial will be divided randomly into two groups. One group will receive the conservative approach: the cavity will be filled with fiber-reinforced composite, and the tooth will be prepared for a lithium disilicate overlay. The other group will follow the conventional method: a fiber post will be placed, a composite build-up added, and finally the tooth will be covered with a full coverage lithium disilicate crown.
The main goal is to see how well each method keeps the tooth intact after six months, using a standard set of criteria to judge success. Other factors will also be checked, such as how well the margins fit, whether there is discoloration or secondary decay, and whether the color matches the surrounding teeth. Importantly, patients will also be asked how satisfied they are with the treatment, using a simple scale to record their feelings.
To make sure the study is fair, patients will be randomly assigned to one of the two groups using a computer program. The operator performing the treatment will know which method is being used, but the patients and the statistician analyzing the results will not, which helps reduce bias. Data will be collected carefully and stored securely. Standard statistical methods will be used to analyze the results, with differences considered significant if the probability of chance is 5% or less.
All patients will sign a consent before joining. Any possible side effects, such as minor discomfort, will be noted. After the six-month follow-up, results will be published in scientific journals and conferences.
By comparing these two approaches, the study hopes to show whether the conservative overlay technique can be a reliable alternative to the traditional crown. If proven successful, this method could help dentists save more of the natural tooth structure, reduce treatment time, and still provide durable, esthetic, and satisfying results for patients.
- Being tested
- Fiber reinforced composite core and an overlay, Fiber post with composite core build up and lithium disilicate full coverage crown
- Keywords
- Lithium Disilicate, Fiber Reinforced Composite, Overlays, Glass Fiber Post, Endodontically Treated Posterior Teeth
- Medical subject headings
- Tooth, Nonvital
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Fiber reinforced composite core and an overlayProcedure or surgery
This intervention implements a restorative approach that combines the mechanical support of a fiber-reinforced composite (FRC) core with the esthetic and durable properties of a lithium disilicate overlay. The FRC core provides internal reinforcement, distributing stresses within the tooth and enhancing fracture resistance, while the lithium disilicate overlay offers high strength, wear resistance, and excellent optical qualities.
Fiber post with composite core build up and lithium disilicate full coverage crownProcedure or surgery
This combines the intraradicular retention of a fiber post with a composite core build-up, providing internal support and reinforcement for compromised teeth. The restoration is completed with a lithium disilicate full coverage crown, offering high strength, durability, and excellent esthetics.
| Study group | Role | What they receive |
|---|---|---|
| Fiber reinforced composite core and lithium disilicate overlay | Active comparator | This arm implements a restorative approach that combines the mechanical support of a fiber-reinforced composite (FRC) core with the esthetic and durable properties of a lithium disilicate overlay. The FRC core provides internal reinforcement, distributing stresses within the tooth and enhancing fracture resistance, while the lithium disilicate overlay offers high strength, wear resistance, and excellent optical qualities. Receives: Procedure: Fiber reinforced composite core and an overlay |
| Fiber post with composite core build up and lithium disilicate full coverage crown | Other | This arm combines the intraradicular retention of a fiber post with a composite core build-up, providing internal support and reinforcement for compromised teeth. The restoration is completed with a lithium disilicate full coverage crown, offering high strength, durability, and excellent esthetics. Receives: Procedure: Fiber post with composite core build up and lithium disilicate full coverage crown |
What is being measured
The primary outcome is the main question the study is designed to answer.
clinical evaluation of tooth integrity
Clinical evaluation of tooth integrity will be measured according to the modified USPHS Criteria having scores of either Alpha, Bravo or Charlie. This will be repeated during the time frame of the Study.
Measured: 6 months
Secondary outcomes (1)
Patient satisfaction
This outcome will be measured through handing the participants a questionnaire addressing the function, color and overall quality and acceptance of the final restorations.
Measured: 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Sep 2026
- Study start20 Sep 2025
- Primary completionJun 2027 (estimated)
- Study completionJun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (5)Papers the sponsor has linked to this study.
- Other trials for Root Canal Treated Posterior TeethStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 50 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Moataz Mostafa Anwar
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Moataz Mostafa Anwar, Cairo University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07836920
- Sponsor's protocol ID
- 2972025
- Status last verified
- Sep 2026
- First submitted
- 14 Sep 2026
- Last updated
- 6 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Zarow M, Vadini M, Chojnacka-Brozek A, Szczeklik K, Milewski G, Biferi V, D'Arcangelo C, De Angelis F. Effect of Fiber Posts on Stress Distribution of Endodontically Treated Upper Premolars: Finite Element Analysis. Nanomaterials (Basel). 2020 Aug 29;10(9):1708. doi: 10.3390/nano10091708.
PubMed 32872519Zarow M, Ramirez-Sebastia A, Paolone G, de Ribot Porta J, Mora J, Espona J, Duran-Sindreu F, Roig M. A new classification system for the restoration of root filled teeth. Int Endod J. 2018 Mar;51(3):318-334. doi: 10.1111/iej.12847. Epub 2017 Sep 25.
PubMed 28853160Iaculli F, Rengo C, Lodato V, Patini R, Spagnuolo G, Rengo S. Fracture resistance of endodontically-treated maxillary premolars restored with different type of posts and direct composite reconstructions: A systematic review and meta-analysis of in vitro studies. Dent Mater. 2021 Sep;37(9):e455-e484. doi: 10.1016/j.dental.2021.06.007. Epub 2021 Jun 18.
PubMed 34148785Ferrari M, Ferrari Cagidiaco E, Goracci C, Sorrentino R, Zarone F, Grandini S, Joda T. Posterior partial crowns out of lithium disilicate (LS2) with or without posts: A randomized controlled prospective clinical trial with a 3-year follow up. J Dent. 2019 Apr;83:12-17. doi: 10.1016/j.jdent.2019.01.004. Epub 2019 Feb 1.
PubMed 30716452Abdel-Maksoud HB, Eid BM, Hamdy M, Abdelaal HM. Optimizing fracture resistance of endodontically treated maxillary premolars restored with preheated thermos-viscous composite post-thermocycling, a comparative study. Part I. BMC Oral Health. 2024 Mar 2;24(1):295. doi: 10.1186/s12903-024-03959-7.
PubMed 38431585
Study at a glance
From the registry record, last updated by the sponsor on 6 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Clinical Evaluation of the Conservative Versus Conventional Restorative Approach for Endodontically Treated Posterior Teeth: A Randomized Clinical Trial
- ClinicalTrials.gov ID
- NCT07836920
- Acronym / sponsor ID
- 2972025
- Keywords
- Lithium Disilicate, Fiber Reinforced Composite, Overlays, Glass Fiber Post, Endodontically Treated Posterior Teeth
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 50 participants (estimated)
- Lead sponsor
- Moataz Mostafa AnwarUniversity, hospital or other
- Study start
- 20 Sep 2025 (actual)
- Primary completion
- Jun 2027 (estimated)
- Study completion
- Jun 2027 (estimated)
- First posted
- 23 Sep 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study compares two methods of restoring posterior teeth after root canal treatment. Traditionally, dentists use fiber posts and full coverage crowns, but this requires removing more tooth structure, which can weaken teeth further. A newer, more conservative option is the overlay, which preserves more of the natural tooth. While overlays appear promising, evidence is still limited, particularly for posterior teeth.
The trial, conducted at Cairo University, will involve fifty patients aged 20-50 with properly root canal treated posterior teeth. Participants will be randomly divided into two groups: one receiving a fiber-reinforced composite with a lithium disilicate overlay (conservative method), and the other receiving a fiber post, composite core, and full coverage lithium disilicate crown (conventional method).
The primary outcome will be tooth integrity after six months, evaluated with standardized criteria. Secondary outcomes include margin quality, discoloration, secondary decay, color matching, and patient satisfaction. Patients will be blinded to the treatment they receive, and data will be analyzed using appropriate statistical methods.
Detailed description
This research protocol explores two different ways of restoring posterior teeth after root canal treatment. Teeth that have had root canal treatment often become weaker because part of their natural structure is removed, and the dentin itself becomes more fragile. As a result, these teeth are more likely to break. Dentists have usually treated this problem by placing a fiber post inside the root canal and then covering the tooth with a full coverage crown. This method has worked well, but it involves drilling inside the root canal, which can make the tooth weaker on the long run.
With advances in modern dentistry, new techniques aim to be more conservative; they try to save as much of the natural tooth as possible. One of these approaches is the overlay, a type of partial coverage restoration that seats on top of the tooth but does not require as much removal of healthy structure as a full coverage crown. Recent studies suggest that overlays can perform just as well as crowns, but there is still not enough strong clinical evidence to confirm this for all cases, especially for posterior teeth that face heavy biting forces. This trial will help fill that gap in the literature.
The study will take place at the Faculty of Dentistry, Cairo University, and will include fifty patients aged between 20 and 50 years. All patients must have had root canal treatment on a restorable posterior tooth. Those with poorly treated canals, cracked teeth, gum disease, or bruxism will not be included. Patients who join the trial will be divided randomly into two groups. One group will receive the conservative approach: the cavity will be filled with fiber-reinforced composite, and the tooth will be prepared for a lithium disilicate overlay. The other group will follow the conventional method: a fiber post will be placed, a composite build-up added, and finally the tooth will be covered with a full coverage lithium disilicate crown.
The main goal is to see how well each method keeps the tooth intact after six months, using a standard set of criteria to judge success. Other factors will also be checked, such as how well the margins fit, whether there is discoloration or secondary decay, and whether the color matches the surrounding teeth. Importantly, patients will also be asked how satisfied they are with the treatment, using a simple scale to record their feelings.
To make sure the study is fair, patients will be randomly assigned to one of the two groups using a computer program. The operator performing the treatment will know which method is being used, but the patients and the statistician analyzing the results will not, which helps reduce bias. Data will be collected carefully and stored securely. Standard statistical methods will be used to analyze the results, with differences considered significant if the probability of chance is 5% or less.
All patients will sign a consent before joining. Any possible side effects, such as minor discomfort, will be noted. After the six-month follow-up, results will be published in scientific journals and conferences.
By comparing these two approaches, the study hopes to show whether the conservative overlay technique can be a reliable alternative to the traditional crown. If proven successful, this method could help dentists save more of the natural tooth structure, reduce treatment time, and still provide durable, esthetic, and satisfying results for patients.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Fiber reinforced composite core and lithium disilicate overlay | Active comparator | Procedure: Fiber reinforced composite core and an overlayThis arm implements a restorative approach that combines the mechanical support of a fiber-reinforced composite (FRC) core with the esthetic and durable properties of a lithium disilicate overlay. The FRC core provides internal reinforcement, distributing stresses within the tooth and enhancing fracture resistance, while the lithium disilicate overlay offers high strength, wear resistance, and excellent optical qualities. |
| Fiber post with composite core build up and lithium disilicate full coverage crown | Other | Procedure: Fiber post with composite core build up and lithium disilicate full coverage crownThis arm combines the intraradicular retention of a fiber post with a composite core build-up, providing internal support and reinforcement for compromised teeth. The restoration is completed with a lithium disilicate full coverage crown, offering high strength, durability, and excellent esthetics. |
Who may qualify
- Ages
- 20 to 50 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (7 listed)
- Patients 20-50 years of age
- Root canal treated posterior teeth
- Good C/R ratio
- Good quality root canal treatment (adequate working length, absence of post operative complications or pain and adequate follow up period)
- Presence of adequate labial and palatal wall thickness
Key exclusion criteria (9 listed)
- Improper root canal treatment
- Post operative complications.
- Cracked teeth
- Parafunctional habits (bruxism)
- Wear pattern
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Fiber reinforced composite core and an overlayThis intervention implements a restorative approach that combines the mechanical support of a fiber-reinforced composite (FRC) core with the esthetic and durable properties of a lithium disilicate overlay. The FRC core provides internal reinforcement, distributing stresses within the tooth and enhancing fracture resistance, while the lithium disilicate overlay offers high strength, wear resistance, and excellent optical qualities. | Procedure or surgery | Fiber reinforced composite core and lithium disilicate overlay |
| Fiber post with composite core build up and lithium disilicate full coverage crownThis combines the intraradicular retention of a fiber post with a composite core build-up, providing internal support and reinforcement for compromised teeth. The restoration is completed with a lithium disilicate full coverage crown, offering high strength, durability, and excellent esthetics. | Procedure or surgery | Fiber post with composite core build up and lithium disilicate full coverage crown |
Primary outcome
clinical evaluation of tooth integrity
Time frame: 6 months
Clinical evaluation of tooth integrity will be measured according to the modified USPHS Criteria having scores of either Alpha, Bravo or Charlie. This will be repeated during the time frame of the Study.
1 secondary outcome
Patient satisfaction
Time frame: 6 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Oct 2026.
- Results publication: PubMed 32872519Zarow M, Vadini M, Chojnacka-Brozek A, Szczeklik K, Milewski G, Biferi V, D'Arcangelo C, De Angelis F. Effect of Fiber Posts on Stress Distribution of Endodontically Treated Upper Premolars: Finite Element Analysis. Nanomaterials (Basel). 2020 Aug 29;10(9):1708. doi: 10.3390/nano10091708.
- Results publication: PubMed 28853160Zarow M, Ramirez-Sebastia A, Paolone G, de Ribot Porta J, Mora J, Espona J, Duran-Sindreu F, Roig M. A new classification system for the restoration of root filled teeth. Int Endod J. 2018 Mar;51(3):318-334. doi: 10.1111/iej.12847. Epub 2017 Sep 25.
- Results publication: PubMed 34148785Iaculli F, Rengo C, Lodato V, Patini R, Spagnuolo G, Rengo S. Fracture resistance of endodontically-treated maxillary premolars restored with different type of posts and direct composite reconstructions: A systematic review and meta-analysis of in vitro studies. Dent Mater. 2021 Sep;37(9):e455-e484. doi: 10.1016/j.dental.2021.06.007. Epub 2021 Jun 18.
- Results publication: PubMed 30716452Ferrari M, Ferrari Cagidiaco E, Goracci C, Sorrentino R, Zarone F, Grandini S, Joda T. Posterior partial crowns out of lithium disilicate (LS2) with or without posts: A randomized controlled prospective clinical trial with a 3-year follow up. J Dent. 2019 Apr;83:12-17. doi: 10.1016/j.jdent.2019.01.004. Epub 2019 Feb 1.
- Results publication: PubMed 38431585Abdel-Maksoud HB, Eid BM, Hamdy M, Abdelaal HM. Optimizing fracture resistance of endodontically treated maxillary premolars restored with preheated thermos-viscous composite post-thermocycling, a comparative study. Part I. BMC Oral Health. 2024 Mar 2;24(1):295. doi: 10.1186/s12903-024-03959-7.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Fiber reinforced composite core and an overlay and Fiber post with composite core build up and lithium disilicate full coverage crown in people with Root Canal Treated Posterior Teeth and Endodontically-Treated Teeth, run by Moataz Mostafa Anwar at 1 site in Egypt.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 6 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Egypt. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Moataz M Anwar, MSC (+201000395041, moataz.mostafa@dentistry.cu.edu.eg), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
clinical evaluation of tooth integrity (time frame: 6 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07836920, which also lists 5 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Oct 2026.