Comparison of the fracture resistance of three different recent composite systems in large Class II mesio-occlusal distal cavities: An in vitro study

BACKGROUND: The present study was undertaken to evaluate the most suitable recent restorative material for extensively mutilated teeth. AIM: This study aims to evaluate and compare the fracture resistance of maxillary premolars with Class II mesio-occlusal distal (MOD) cavities restored with recent Ever X posterior, bulk-fill composite, and Estelite sigma quick composite systems. MATERIALS AND METHODS: Sixty human maxillary premolars were selected. Fifteen intact teeth served as positive control (Group 1). MOD cavities were prepared in the remaining 45 teeth with standardized dimensions and were randomly divided into three experimental groups (Group 2, 3, and 4) (n = 15). Teeth in Group 2, 3, and 4 were reinforced with 3M ESPE Filtek Bulk-fill posterior, GC Ever X posterior, and Tokuyama Estelite sigma quick composites, respectively. Fracture resistance was measured in Newton (N). RESULTS: Group 4 (1432.60 N) showed the highest mean fracture resistance followed by Group 3 (1326.20 N), Group 1 positive controls (1288.53 N), and Group 2 (946.66N), respectively. One-way analysis of variance (ANOVA) test revealed a statistically significant difference between all the groups (P = 0.005). Post hoc Tukey test revealed a statistically significant difference in mean fracture resistance between the Group 2 and Group 4 (P = 0.004), as well as between the Group 2 and Group 3 (P = 0.033). However, there were no significant differences among the other groups. CONCLUSION: Among the experimental groups, Estelite sigma quick composite showed the highest fracture resistance. Statistically, a significant difference was seen between all groups.