Evaluation of the Clinical Success of Direct Restorations of Endodontically Treated Posterior Teeth in the Presence of Parafunction: A Pilot Study

The aim of this prospective, randomized, parallel-group clinical study is to compare the 6- and 12-month clinical performances of direct composite restorations applied to endodontically treated posterior teeth with or without the use of fiber-reinforced composite material in individuals with parafunctional habits.

Bruxism is a repetitive jaw-muscle activity characterized by clenching and/or grinding of teeth. The possible outcomes of bruxism include wear and/or fractures in the teeth and restorations. Therefore, the choice of restorative methods and materials for restorations in bruxist individuals is of great importance. Direct adhesive restorations are the first treatment option for endodontically treated teeth with no excessive material loss and/or those that have lost vitality due to trauma. Over the past decade, the use of fiber-reinforced materials has been recommended to prevent catastrophic fractures. Fiber-reinforced materials have been developed and introduced to the market based on the idea that a restorative material that distributes or absorbs stress in high-stress areas will protect the underlying tooth structure.

Although there are numerous studies on the mechanical durability of restorative treatments for endodontically treated teeth in cases with parafunctional habits, there are limited clinical studies regarding the clinical performance of these methods.

The study included 32 premolar or molar teeth with Class 1 and Class 2 cavity types and a remaining wall thickness of at least 3 mm, which had undergone endodontic treatment from volunteer participants. The teeth randomly assigned were divided into two groups (n=16): Group 1: fiber-reinforced composite restoration (EverX flow, GC) (FRCR), Group 2: composite restoration (Gneal Posterior, GC) (CR). The restorations were evaluated at 6 and 12 months using the FDI criteria.