Relative Microhardness and Flexural Strength of Different Bulk Fill Resin Composite Restorative Materials

Aim: to find out if there is a significant difference in the curing efficiency at the claimed 4 mm depth and in the mechanical properties between the tested pasteform bulk fill resin composite materials. Materials and Methods: Three paste-consistency bulk-fill resin composites were used in this study (Filtek bulk fill3M; X-trafilVoco; and SonicFill bulk-fillKerr). For the microhardness testing, standardized disc-shaped resin composite samples (6mm X 4mm) were prepared. For the Flexural Strength testing, standardized resin composite samples with the dimensions of (2mm x 2mm x 25mm) were fabricated.All samples were light cured following the manufacturers’ instructions using high intensity LED light-curing unit.Five samples were prepared from each material for each test with a total of 30 samples (15 for each test). Both tests were run at baseline after preparing the specimens without storage. Vickers microhardness values of the top and bottom surfaces were recorded. Three-point flexural strength test values were recorded. One-way ANOVA test statistics was done to compare between the mean values for the 3 materials with p value less than 0.05. Least significance test was followed to compare between each two materials in case statistical significance was found. Results: 3M had statistically significant lower surface microhardness values on both surfaces (top and bottom) at p< 0.05. All the three bulk fill resin composite materials showed sufficient relative microhardness values (>0.80) at 4 mm depth. 3M had the lowest mean flexural strength value and SonicFill had the highest mean flexural strength value but the difference is not statistically significant at p< 0.05.Conclusion:Microhardness values of paste consistency bulk fill materials can differ compared to each other but all showed sufficient depth of cure at 4 mm depth and no significant difference in their flexural strength. [Reem Ali Ajaj. Relative Microhardness and Flexural Strength of Different Bulk Fill Resin Composite Restorative Materials.J Am Sci2015;11(7):155-159]. (ISSN: 1545-1003). http://www.jofamericanscience.org.19