Evaluation of the Compressive and Diametric Tensile Strength of Two Type Nano and Two Type Hybrid Composites

Restorative materials should be able not to strain under pressure during restoration process or mastication, so their mechanical properties are of high importance. The aim of this study was to evaluate the compressive and diametric tensile strength of hybrid and nanofilled composite restorative materials. Two hybrids (Diafil & Spectrum) and two nanofilled composite (nex com & synergy nano) were used in this in vitro experimental study. Samples were placed in a special circular mold and were light cured. After removing, the samples were stored in a light proof container under distilled water for 1 week. The specimens were then submitted to compressive and diametric tensile test, using universal compression machine at a crosshead speed of 1 mm/min. Data were analyzed using ANOVA and Duncan tests at significant level of 0.05. There was not any significant difference between the values of compressive strengths of the composites (P>0.05). Nex comp showed the least diametric tensile strength (P<0.05), but no significant difference was detected between the other three materials. Compressive strength of various composites was about the same, but diametric tensile strength of Nexcomp nanofilled composites was lower than other nanofilled or hybrid composites.