Dental Restoration FailureDWTNCT07917572
The Effect of Decoupling With Time Technique on the Clinical Performance of Proximal Posterior Composite Restorations
A study testing Decoupling With Time Technique and Conventional Composite Restoration in people with Dental Restoration Failure and Postoperative Hypersensitivity, run by Cairo University.
Trial summary
This randomized clinical trial will evaluate whether the decoupling with time technique improves the clinical performance of Class II posterior composite restorations compared with conventional composite restoration techniques. Read more about this study
- Who is it for?
- Ages 20 to 40 years
- Conditions the study is for
- Dental Restoration Failure, Postoperative Hypersensitivity
- What is being tested?
- Decoupling With Time Technique and Conventional Composite Restoration
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 50 participants
- Where
- No sites listed yet
- Study dates
- 1 Nov 2026to 1 May 2028
- 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 40 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Patients aged between 20 and 40 years.
- Patients with posterior carious Class II lesions.
- Good oral hygiene.
- Favorable occlusion.
- Absence of deleterious oral habits.
Who cannot join
- Teeth showing signs of irreversible pulpitis.
- Teeth with secondary caries.
- Teeth with old restorations.
- Endodontically treated teeth.
- Patients with a history of adverse reactions to the test material.
- Patients with poor oral hygiene.
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- Patients with systemic disease.
- Patients with severe periodontal disease.
- Uncooperative patients.
- Patients unable to attend the scheduled recall visits.
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
Mahetab Mahmoud Abd Elhameed, Master's candidate contact
About this study
Official title: The Effect of Decoupling With Time Technique on the Clinical Performance of Proximal Posterior Composite Restorations: An 18-Month Randomized Clinical Trial
This randomized clinical trial will evaluate whether the decoupling with time technique improves the clinical performance of Class II posterior composite restorations compared with conventional composite restoration techniques. The study will also assess postoperative hypersensitivity and the additional operative time required to perform the decoupling with time technique. Participants will receive a posterior composite restoration and will be followed for 18 months. Clinical performance will be evaluated using the Modified United States Public Health Service (USPHS) criteria, and postoperative hypersensitivity will be assessed before treatment, 1 week after restoration placement, and at 6, 12, and 18 months. The study will help determine whether the additional time required for the decoupling with time technique is associated with improved clinical outcomes.
Read the detailed description
This randomized clinical trial will evaluate the effect of the decoupling with time technique on the clinical performance of posterior composite restorations in Class II cavities.
The study will include eligible participants requiring posterior Class II composite restorations. Participants will be randomly allocated to either the decoupling with time group or the conventional restoration group.
In the decoupling with time group, following cavity preparation, immediate dentin sealing will be performed using a universal adhesive system applied with a selective enamel-etching strategy. A conventional flowable resin composite will then be applied as an initial stress-reducing layer with a thickness of approximately 0.5-1.0 mm. A 5-minute waiting period will be allowed before completion of the composite restoration. Deep margin elevation will not be performed as part of the study protocol.
The control group will receive a conventional posterior composite restoration according to the standardized restorative protocol without the decoupling with time waiting period.
The primary outcome will be postoperative hypersensitivity, assessed using the Modified United States Public Health Service (USPHS) criteria. Hypersensitivity will be assessed pre-operatively, at 1 week after restoration placement, and at 6, 12, and 18 months after restoration placement.
The clinical performance of the restorations will be evaluated using the Modified USPHS criteria immediately after restoration placement and at 6, 12, and 18 months. The evaluated clinical parameters will include marginal integrity, fracture and retention, marginal discoloration, anatomic form, proximal contact, surface texture, radiographic evaluation, and secondary caries.
The total operative time required to complete each restoration will also be recorded in minutes using a digital stopwatch, starting from the beginning of the restorative procedure and ending upon completion of the restoration. This will allow assessment of whether the additional operative time associated with the decoupling with time technique is associated with improved clinical outcomes.
Participants will be followed for 18 months to evaluate the clinical performance of the restorations and postoperative hypersensitivity over time.
- Being tested
- Decoupling With Time Technique, Conventional Composite Restoration
- Keywords
- Decoupling with Time, Postoperative Hypersensitivity, Clinical Performance, Immediate Dentin Sealing, Posterior Composite Restorations
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Decoupling With Time TechniqueProcedure or surgery
Immediate dentin sealing using a universal adhesive system with a selective enamel-etching strategy, followed by application of a 0.5-1.0 mm layer of conventional flowable resin composite and a 5-minute waiting period before completion of the posterior composite restoration.
Conventional Composite RestorationProcedure or surgery
Conventional Class II posterior composite restoration without the decoupling with time procedure.
| Study group | Role | What they receive |
|---|---|---|
| Decoupling With Time Group | Experimental | Participants assigned to this group will receive a Class II posterior composite restoration using the decoupling with time technique. Immediate dentin sealing will be performed using a universal adhesive system with a selective enamel-etching strategy, followed by application of a 0.5-1.0 mm layer of conventional flowable resin composite. A 5-minute waiting period will be allowed before completion of the composite restoration. Receives: Procedure: Decoupling With Time Technique |
| Conventional Composite Group | Active comparator | Participants assigned to this group will receive a conventional Class II posterior composite restoration without the decoupling with time procedure or the additional 5-minute waiting period. Receives: Procedure: Conventional Composite Restoration |
What is being measured
The primary outcome is the main question the study is designed to answer.
Postoperative Hypersensitivity
Postoperative hypersensitivity will be assessed clinically using the Modified United States Public Health Service (USPHS) criteria. The assessment will be performed before the restorative procedure and at the specified follow-up visits after restoration placement.
Measured: Pre-operatively, 1 week, 6 months, 12 months, and 18 months after restoration placement.
Secondary outcomes (2)
Clinical Performance of Posterior Composite Restorations
Clinical performance of the restorations will be evaluated using the Modified United States Public Health Service (USPHS) criteria. The evaluated parameters will include marginal integrity, fracture and retention, marginal discoloration, anatomic form, proximal contact, surface texture, radiographic evaluation, and secondary caries.
Measured: Immediately after restoration placement, 6 months, 12 months, and 18 months after restoration placement.
Total Operative Time
The total time required to complete each restorative procedure will be measured in minutes using a digital stopwatch, starting from the beginning of the restorative procedure and ending upon completion of the restoration.
Measured: During the restorative procedure.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Nov 2026
- Study start1 Nov 2026 (estimated)
- Primary completion1 May 2028 (estimated)
- Study completion1 May 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Dental Restoration FailureStudies of the same condition, open and under way.
- More trials run by Cairo UniversityThe sponsor's other registered studies.
- 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
- Cairo University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Mahetab Mahmoud, Cairo University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07917572
- Sponsor's protocol ID
- Cons-DWT-C.Perf-2026
- Acronym
- DWT
- Status last verified
- Oct 2026
- First submitted
- 30 Oct 2026
- Last updated
- 4 Nov 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 4 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effect of Decoupling With Time Technique on the Clinical Performance of Proximal Posterior Composite Restorations: An 18-Month Randomized Clinical Trial
- ClinicalTrials.gov ID
- NCT07917572
- Acronym / sponsor ID
- DWT / Cons-DWT-C.Perf-2026
- Keywords
- Decoupling with Time, Postoperative Hypersensitivity, Clinical Performance, Immediate Dentin Sealing, Posterior Composite Restorations
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 50 participants (estimated)
- Lead sponsor
- Cairo UniversityUniversity, hospital or other
- Study start
- 1 Nov 2026 (estimated)
- Primary completion
- 1 May 2028 (estimated)
- Study completion
- 1 May 2028 (estimated)
- First posted
- 4 Nov 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 randomized clinical trial will evaluate whether the decoupling with time technique improves the clinical performance of Class II posterior composite restorations compared with conventional composite restoration techniques. The study will also assess postoperative hypersensitivity and the additional operative time required to perform the decoupling with time technique. Participants will receive a posterior composite restoration and will be followed for 18 months. Clinical performance will be evaluated using the Modified United States Public Health Service (USPHS) criteria, and postoperative hypersensitivity will be assessed before treatment, 1 week after restoration placement, and at 6, 12, and 18 months. The study will help determine whether the additional time required for the decoupling with time technique is associated with improved clinical outcomes.
Detailed description
This randomized clinical trial will evaluate the effect of the decoupling with time technique on the clinical performance of posterior composite restorations in Class II cavities.
The study will include eligible participants requiring posterior Class II composite restorations. Participants will be randomly allocated to either the decoupling with time group or the conventional restoration group.
In the decoupling with time group, following cavity preparation, immediate dentin sealing will be performed using a universal adhesive system applied with a selective enamel-etching strategy. A conventional flowable resin composite will then be applied as an initial stress-reducing layer with a thickness of approximately 0.5-1.0 mm. A 5-minute waiting period will be allowed before completion of the composite restoration. Deep margin elevation will not be performed as part of the study protocol.
The control group will receive a conventional posterior composite restoration according to the standardized restorative protocol without the decoupling with time waiting period.
The primary outcome will be postoperative hypersensitivity, assessed using the Modified United States Public Health Service (USPHS) criteria. Hypersensitivity will be assessed pre-operatively, at 1 week after restoration placement, and at 6, 12, and 18 months after restoration placement.
The clinical performance of the restorations will be evaluated using the Modified USPHS criteria immediately after restoration placement and at 6, 12, and 18 months. The evaluated clinical parameters will include marginal integrity, fracture and retention, marginal discoloration, anatomic form, proximal contact, surface texture, radiographic evaluation, and secondary caries.
The total operative time required to complete each restoration will also be recorded in minutes using a digital stopwatch, starting from the beginning of the restorative procedure and ending upon completion of the restoration. This will allow assessment of whether the additional operative time associated with the decoupling with time technique is associated with improved clinical outcomes.
Participants will be followed for 18 months to evaluate the clinical performance of the restorations and postoperative hypersensitivity over time.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Decoupling With Time Group | Experimental | Procedure: Decoupling With Time TechniqueParticipants assigned to this group will receive a Class II posterior composite restoration using the decoupling with time technique. Immediate dentin sealing will be performed using a universal adhesive system with a selective enamel-etching strategy, followed by application of a 0.5-1.0 mm layer of conventional flowable resin composite. A 5-minute waiting period will be allowed before completion of the composite restoration. |
| Conventional Composite Group | Active comparator | Procedure: Conventional Composite RestorationParticipants assigned to this group will receive a conventional Class II posterior composite restoration without the decoupling with time procedure or the additional 5-minute waiting period. |
Who may qualify
- Ages
- 20 to 40 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Patients aged between 20 and 40 years.
- Patients with posterior carious Class II lesions.
- Good oral hygiene.
- Favorable occlusion.
- Absence of deleterious oral habits.
Key exclusion criteria (10 listed)
- Teeth showing signs of irreversible pulpitis.
- Teeth with secondary caries.
- Teeth with old restorations.
- Endodontically treated teeth.
- Patients with a history of adverse reactions to the test material.
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 |
|---|---|---|
| Decoupling With Time TechniqueImmediate dentin sealing using a universal adhesive system with a selective enamel-etching strategy, followed by application of a 0.5-1.0 mm layer of conventional flowable resin composite and a 5-minute waiting period before completion of the posterior composite restoration. | Procedure or surgery | Decoupling With Time Group |
| Conventional Composite RestorationConventional Class II posterior composite restoration without the decoupling with time procedure. | Procedure or surgery | Conventional Composite Group |
Primary outcome
Postoperative Hypersensitivity
Time frame: Pre-operatively, 1 week, 6 months, 12 months, and 18 months after restoration placement.
Postoperative hypersensitivity will be assessed clinically using the Modified United States Public Health Service (USPHS) criteria. The assessment will be performed before the restorative procedure and at the specified follow-up visits after restoration placement.
2 secondary outcomes
Clinical Performance of Posterior Composite Restorations
Time frame: Immediately after restoration placement, 6 months, 12 months, and 18 months after restoration placement.
Total Operative Time
Time frame: During the restorative procedure.
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 4 Nov 2026.
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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.
Mahetab Mahmoud Abd Elhameed, Master's candidate contact
Questions about this trial
What is this clinical trial studying?
A study testing Decoupling With Time Technique and Conventional Composite Restoration in people with Dental Restoration Failure and Postoperative Hypersensitivity, run by Cairo University.
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 5 inclusion and 10 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: opening soon, as of the sponsor's last update on 4 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
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 Mahetab Mahmoud Abd Elhameed, Master's candidate (201151895247, mahetab.mahmoud@dentistry.cu.edu.eg), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Postoperative Hypersensitivity (time frame: Pre-operatively, 1 week, 6 months, 12 months, and 18 months after restoration placement.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 4 Nov 2026.