Fiber-reinforced composite restorations in endodontically treated teeth under functional loading.

Endodontically treated teeth remain highly susceptible to fracture due to significant loss of structural integrity and optimal restorative material selection remains a clinical challenge. Therefore, it is of interest to evaluate fracture resistance, marginal adaptation and microleakage of fiber-reinforced composite (FRC) restorations compared with conventional composite and metal-ceramic crowns under simulated functional loading. Ninety extracted human premolars were randomly assigned to three groups and subjected to cyclic loading (200 N, 500,000 cycles) using a chewing simulator. FRC restorations demonstrated significantly higher fracture resistance (987.4 ± 62.3 N) compared to conventional composite (743.2 ± 58.1 N) and showed comparable marginal adaptation to metal- ceramic crowns (p<0.001). Fiber-reinforced composites may provide a biomechanically superior and clinically viable alternative for restoring endodontically treated teeth, particularly in high load-bearing posterior regions.