Effect of Different Cavity Designs on the Clinical Performance of 3D- Printed Resin Composite Partial-Coverage Restorations in Vital Molars

NCT07667946 | Not Yet Recruiting DMC

• 1 other identifier: Effect of Cavity Designs
• Study Type: interventional
• Target: 50
• Locations: 0 countries
• Sites: N/A

Brief Summary

This randomized clinical trial aims to evaluate the effect of different cavity designs on the clinical performance of 3D-printed resin composite partial-coverage restorations in vital molars with complex cavities over an 18-month follow-up period.

Conditions

Clinical Performance

Outcome Measures

Primary Outcomes (1)

• Fracture

  Modified USPHS Ryge Criteria (Ordinal scoring system)

  18 Months

Secondary Outcomes (1)

• Retention, marginal integrity, marginal discoloration, wear/anatomic form, secondary caries and surface texture

  18 Months

Study Arms (2)

Anatomical cavity design preparation

EXPERIMENTAL

Following caries excavation and removal of defective restorations, cavity preparations will be carried out according to the accepted principles of adhesive overlays. The cavity walls will be prepared with 6-12° internal axial wall divergence using blue-coded tapered round-end diamond burs (Komet, USA) and subsequently finished using extra-fine yellow-coded tapered round-end diamond burs (#368EF, Komet, USA). The thickness of potentially maintainable cusps will be assessed using a dental caliper (Diamonds Surgical Instruments, Pakistan). Weakened or undermined cusps (less than 2 mm thickness) will be reduced using the same diamond burs to create an anatomical occlusal reduction following the natural tooth morphology, with a reduction of 2 mm.

Procedure: Anatomical cavity design preparation

Butt joint cavity design preparation

ACTIVE COMPARATOR

The cavity walls will be prepared with 6-12° internal axial wall divergence using blue-coded tapered round-end diamond burs (Komet, USA) and subsequently finished using extra-fine yellow-coded tapered round-end diamond burs (#368EF, Komet, USA). The thickness of potentially maintainable cusps will be assessed using a dental caliper (Diamonds Surgical Instruments, Pakistan). The occlusal reduction design, where weakened or undermined cusps will be reduced using a wheel stone (#909, Komet, USA) to create a flat butt-joint occlusal design with a uniform occlusal reduction of 2 mm. Additional reduction will be performed when necessary, and the available interocclusal clearance will be verified using a graduated periodontal probe in maximum intercuspation and eccentric movements.

Procedure: Butt joint cavity design preparation

Interventions

Anatomical cavity design preparation PROCEDURE

Cavity preparation design for adhesive restoration

Anatomical cavity design preparation

Butt joint cavity design preparation PROCEDURE

Cavity preparation design for adhesive restoration

Butt joint cavity design preparation

Eligibility Criteria

• Age: 20 Years - 45 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Adult patients aging 20-45 years.
• Healthy males and females
• Patients with good oral hygiene
• Patients presenting with at least one eligible permanent molar requiring a partial-coverage restoration.
• Patients willing and able to attend scheduled follow-up visits for 18 months.
• Permanent maxillary or mandibular molars.
• Vital teeth with a positive response to cold thermal testing.
• Complex Large or severely compromised cavities resulting from primary or secondary caries (ICDAS 5 or 6) and/or replacement of large defective restorations with at least 2 missing cavity walls requiring overlay restorations
• Well-formed and fully erupted in normal functional occlusion with natural antagonist and adjacent teeth.
• Absence of any radiographic, periodontal or periapical changes.

You may not qualify if:

• Participants with general/systemic illness.
• Pregnant or lactating females.
• Concomitant participation in another research study.
• Inability or unwillingness to comply with study visits and procedures.
• Heavy bruxism or other parafunctional habits
• Known allergic reactions against any components of the used materials
• Patients receiving orthodontic treatment.
• Poor oral hygiene or high caries activity.
• Non vital teeth.
• Hypersensitive teeth.
• Teeth with prior endodontic treatment.
• Teeth with spontaneous pain or signs/symptoms of irreversible pulpitis.
• Teeth with advanced periodontal disease or mobility.
• Teeth with a history of direct or indirect pulp capping procedure.
• Teeth with vertical root fractures or cracked tooth syndrome

Sponsors & Collaborators

• Cairo University: lead

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, OUTCOMES ASSESSOR
• Masking Details: Triple blinded
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: PhD candidate

Model Details: Randomized clinical trial (RCT), triple blinded, parallel groups, two arms, superiority study with 1:1 allocation ratio.

Study Record Dates

• First Submitted: June 19, 2026
• First Posted: June 25, 2026
• Study Start: July 1, 2026
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): January 1, 2028
• Last Updated: June 25, 2026

Record last verified: 2026-06