Vickers microhardness comparison of 4 composite resins with different types of filler.

Composite resins are the material election to restored minimal invasive cavities; conversely, it is important to explore their mechanical properties of commercial available dental materials. Objective: To compare the Vickers microhardness (VHN) of four available commercial composite resins of standardized samples and methods. Methodology: Composite cylinders were performed in a Teflon mould. We use the follow composite resins (n=4/gp): Microhybrid resins [Feeling Lux (Viarden) and Amelogen Plus (Ultradent)], Hybrid resin [Te-Econom Plus (Ivoclar)] and Nanohybrid resin [Filtek Z350 (3M ESPE)]. All samples were incubated in distilled water at 37 oC for five days. The test was carried out with microhardness indenter at 10 N, and a dwelling time of 10 s for 9 indentations across the specimens resulting in a total of 36 indentations for each group. Data were subject to Kolmogorov-Smirnov normality test and ANOVA (post-hoc) Tukey test. Results: The VHN mean values corresponded from harder to softer as follow: Filtek Z350 (71.96±6.44) (p˂0.01)˃Amelogen Plus (59.90±4.40) (p˂0.05)˃Feeling lux (53.52±5.72)˃Te-Econom Plus (53.26±5.19). Conclusion: According to our results, the microhardness of the evaluated conventional composite resin can withstand the masticatory forces but nanohybrid composite resins showed better Vickers microhardness that clinically can results in suitable option for restored minimal invasion treatments.