Fatigue Resistance of Resin Composite Materials

Objectives: Clinicians have a wide selection of restorative composites for the restoration of force-bearing restorations. The aim of this study is to evaluate the fatigue performance of current composite resins using a four point bending setup.
Methods: Methods: Rectangular beams with dimensions of 2x2x12 mm were used. AP-X (Kuraray), Filtek Z250 (3M ESPE), Filtek Supreme XTE (3M), Sonicfill 2 (Kerr), Venus Bulk Fill (Heraus Kulzer), Filte Bulk Fill Posterior Restorative (3M), Tetric EvoCeram Bulk Fill (Ivoclar Vivadent), GC everX Posterior (GC) and SDR (Dentsply) were used in the study. The specimens were polymerized according to the manufacturers’ recommendations and aged in distilled water for one month at room temperature before testing. The specimens were subjected to either quasi-static (N=10) or cyclic (N=20) four-point flexure testing using a stress ratio of 0.1 and a frequency of 5 hertz to failure in fully hydrated conditions. The specimens were loaded untilfailure or the test was stopped at 1.2 million cycles. Data was analyzed using one-way ANOVA for quasi-static and Wilcoxon Rank Sum test for fatigue data (α=0.05).
Results: Flexural strength data were given in the Table. For fatigue data, no significant difference was found among the bulk groups (p=0.39). However, conventional composites were significantly higher than the bulk materials (p<0.05).
Conclusions: Conventional resin composites have superior mechanical properties than the recently introduced bulk composites.