Fracture resistance of teeth restored with different resin-based restorative systems

the aim of the present study was to evaluate the fracture resistance of teeth restored with resin composite. forty-eight maxillary premolar teeth were chosen and randomly divided to six groups: g1 (control): sound teeth; g2: mod preparation, unrestored; g3: mod + adper single bond 2/p60; g4: mod + adper easy one/p60; g5: mod + p90 restorative system; g6: mod + adper easy one/p90 bond/p90. specimens were subjected to compressive axial loading (0.5 mm/min). flexural strength and the modulus of elasticity were also tested (n = 7). the only statistical equivalence with sound teeth was noted for g3 (p < 0.05). flexural strength and the modulus of elasticity varied among the composites tested (n = 10). the reestablishment of the resistance to fracture in premolars subjected to class ii mod preparations is restorative-system-dependent. the silorane restorative system is not able to recover the resistance to fracture.