This Study is Conducted to Evaluate the Clinical Performance of Indirect Overlay Restorations With Different Cavity Preparation Designs in Endodontically Treated Molars.

May 22, 2026 updated by: Sara Ibrahim Mohamed Fahmy, Cairo University

A Prospective Clinical Evaluation of Indirect Overlay Restorations With Different Cavity Preparation Designs in Endodontically Treated Molars: Two Year Randomized Clinical Trial

This study is conducted to evaluate the clinical performance of indirect overlay restorations with different cavity preparation designs in endodontically treated molars over two years.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Not yet recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

First Validation of endodontic treatment using a periapical radiograph and proper history taking.

{I}• Cavity Preparation Procedures for Comparator Group:

  • Removal of any remnants of temporary filling and excess gutta percha to the level of root canal orifice.
  • Removal of all undermined enamel.
  • Then 1.5 to 2 mm cusp reduction will be performed for the buccal and lingual walls.
  • The occlusal box will be of 2.5 mm width, 2 mm depth cavity walls and will be flared to produce a 6 degree of divergence.
  • The cavity will have internal rounded angles, finished enamel with sharp non-beveled margins and smooth well-defined walls.
  • Immediate Dentin Sealing and Cavity Optimization: Immediate dentin sealing will be performed through the use of a universal adhesive followed by the injection of injectable flowable resin composite. Blocking of undercuts using injectable flowable resin composite and margin elevation if required.
  • The final retentive design will include occlusal clearance of 2 mm with occlusal box cavity of depth 2 mm with all margins in enamel occlusally and all dentin surfaces will be covered.

{II}• Cavity Preparation Procedures for Intervention Group:

  • Removal of any remnants of temporary filling and excess gutta percha to the level of root canal orifice.
  • No additional removal of the tooth structure will be performed at this step.
  • Cavity optimization will be performed first.
  • Blocking of undercuts using injectable flowable resin composite and margin elevation if required.
  • The occlusal cavity will be restored during cavity optimization with injectable resin composite to reduce the areas of dentin exposure and preserve the remaining tooth structure.
  • The dentin substitute resin composite will establish the biobase.
  • An anatomical non retentive preparation design will be performed to show continuous inclined plane preparation with 2 mm cuspal reduction, concave chamfer margins, and 1 to 1.5 mm thick butt-joint preparation in the interproximal portion.

  • The final cavity design will include occlusal clearance of 2 mm with total cusp coverage, with biomimetic features (anatomical, non-retentive design) with no occlusal box cavity.

    • The CAD/CAM partial coverage overlay restoration will be designed, then milled using SHOFU Hard hybrid ceramic blocks for both groups following its design.
    • Cementation for both groups:
  • Selective etching of the enamel margins of the cavity will be made using 37% phosphoric acid.
  • Application of Universal Adhesive according to manufacturer's instructions and cured.
  • Regarding the milled indirect overlay restorations; surface roughening with Dura-Green Stones SHOFU will be performed, followed by the application of a suitable priming agent, then the injection of resin cement in the fitting surface, and finally the restoration will be cemented.
  • Restoration will be placed onto the prepared cavities allowing for excess resin cement to emerge which will then be tac-cured for 5 second using a standard intensity light cure allowing for slight hardening of the excess resin cement.
  • Removal of excess cement using a sharp explorer, excavator or a c-blade along with the use of interdental flossing to ensure elimination of interdental excess resin cement material.
  • Completing the remaining curing cycle after excess removal to the full curing time.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
50

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

Patient Related Criteria:

  • Adult patients (age: 20-60 years) of both genders.
  • Healthy patients (not suffering of any systematic or chronic diseases).
  • Able to tolerate the necessary restorative procedures.
  • Willing to sign the informed ethical consent.
  • Accepts the follow-up period.

Tooth Related Criteria:

  • Proper endodontically treated teeth.
  • First and second permanent molars.
  • Absence of any peri-apical lesions.
  • Absence of any periodontal disease involvement.
  • Large access cavities with one or two missing walls.
  • Patients with proper oral hygiene.
  • Presence of opposing tooth.

Exclusion Criteria:

  • Patient related:
  • Patients younger than 20 or older than 60 years old.
  • Pregnant females.
  • Patients with any systemic or chronic diseases.
  • Patients not accepting the follow-up period.
  • Patients not willing to sign the informed ethical consent.
  • Patients with known allergies to latex and/or resinous material.

Tooth related

  • Endodontically treated anterior, premolar and third molar teeth.
  • Hopelessly carious/destructed teeth necessitating extraction.
  • Mobile teeth, indicating periodontal disease or trauma.
  • External or internal resorption.
  • Poor endodontic treatment.
  • Periapical lesion present.
  • Cervical carious lesions involved.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: conventional retentive overlay design
Other: hybrid ceramic retentive overlay
Endodontically treated molars will receive indirect overlay restorations utilizing a conventional retentive occlusal box cavity design.
Experimental: minimal invasive non-retentive overlay design
Other: hybrid ceramic non-retentive overlay
Endodontically treated molars will receive indirect overlay restorations utilizing a minimal invasive anatomical non-retentive design.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Marginal adaptation (success rate)
Time Frame: T0: baseline T1: 6 months T2: 12 months T3: 18 months T4: 2 years

Measuring device:

Modified FDI criteria,

Measuring unit:

Ordinal Data (scores)
T0: baseline T1: 6 months T2: 12 months T3: 18 months T4: 2 years

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
proximal contact point 3.fracture of material and retention 4.wear 5. marginal staining 6. color match 7.caries at restoration margin
Time Frame: T0: baseline T1: 6 months T2: 12 months T3: 18 months T4: 2 years

Measuring device:

Modified FDI criteria,

Measuring unit:

Ordinal Data (scores)
T0: baseline T1: 6 months T2: 12 months T3: 18 months T4: 2 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Cairo University

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Study Director: Olfat ElSayed Hassanein, Professor, Conservative Dentistry, Faculty of Dentistry, Cairo University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
June 15, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
June 15, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
August 15, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
May 19, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
May 22, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
May 29, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
May 29, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
May 22, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
April 1, 2026

More Information

Terms related to this study

Keywords

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 12041994

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Endodontically Treated Molar

Clinical Trials on hybrid ceramic retentive overlay

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings