Clinical Performance of Milled Resin Composite in Restoration of Endodontically Treated Posterior Teeth Over One Year

The study will be conducted in Conservative Dentistry Department, Faculty of Dentistry, Cairo University; The operator in charge will be Esraa Esmeail Hussien.

Null-hypothesis: There are no differences in the clinical performance of indirect CAD/CAM milled composite when compared to direct bulk-fil composite endocrowns when in the posterior area.

Aim: This clinical trial will be conducted to assess the clinical performance of using indirect Milled composite or direct bulk-fill resin composite Endo-crowns for restoring the endo-treated teeth, as well to measure the amount of wear on the occlusal tables of both restorations using Digital Scanner.

Patients will be selected from the outpatient clinic of the department Conservative Dentistry Department, Faculty of Dentistry, Cairo University

Clinical Steps:

• A tapered stone with rounded end in a high-speed handpiece with air /water coolant will be used to properly prepare the cavity walls to receive the indirect restoration and any remaining carious dentin will be excavated and removed.
• Cuspal tipping will be done by a wheel stone about 1.5-2mm.
• The entrance to the pulpal canal will be opened. Gutta percha will be removed to a depth not exceeding 2 mm to take advantage of the saddle-like anatomy of the cavity floor. This should be done with a nonabrasive instrument to maintain the integrity of the canal's entrance. No drilling into the dentin will be carried out.
• Any remaining undercuts will be blocked with conventional resin composite.
• The impression will be taken, and the final restoration will be fabricated either direct or indirect.
• The final restoration should be checked intraorally for proximal contacts, occlusion and marginal fit before cementation.
• Isolation of operatory field using rubber dam.
• Selective enamel etching technique will be applied for bonding of tooth structure, 35-40% phosphoric acid gel will be applied to the enamel margins only for 15 seconds, rinsed for 15 seconds and gently dried by cotton pellet.
• Adhesive will be used according to the manufacturers' instructions.
• Adhesive resin cement will be applied into the preparation. The restoration will be placed in the cavity and checked for complete seating. The cement will be light cured for only 2 seconds to facilitate removal of the excess. Then light curing will be done from all directions each for 40 seconds for achieving the final set.
• The proximal contacts will be checked with dental floss.
• The occlusion will be adjusted using articulating paper.
• Finishing and Polishing using finishing stones and polishing rubber points.

Primary Objective: To evaluate clinical performance of different Techniques of Composite Restorations (Indirect restorations using a CAD/CAM grinding process, BRILLIANT Crios, Coltène/Whaledent AG, Switzerland or Direct a light-cured, bulk-fill nanocomposite restorative material, Filtek™ One Bulk Fill Restorative, 3M ESPE Dental Products, USA) in Endodontically treated posterior teeth.

Inclusion criteria

of participants:

• Patients with asymptomatic endodontically treated molars.
• Males or Females.
• Good oral hygiene.
• Co-operative patients approving to participate in the study.

Inclusion criteria

of teeth:

• Asymptomatic endodontically treated upper or lower molars with
• Homogenous root canal filling ending 1-2mm from the radiographic apex.
• Proximal compound cavities.
• Favorable occlusion.

Exclusion criteria

of participants:

• High caries index with poor oral hygiene.
• Severe medical complications.
• Pregnancy.
• Allergic history concerning methacrylates Disabilities.
• Heavy smoking.
• Xerostomia.
• Lack of compliance.
• Evidence of parafunctional habits.
• Temporomandibular joint disorders.

Exclusion criteria

of the teeth:

• Teeth with remaining wall thickness less than 1mm.
• Teeth with improper or symptomatic endodontic treatment.
• Deep subgingival cavity margins.
• Possible future prosthodontic restoration of teeth.
• Severe periodontal problems.