Mechanical properties of three composite resins for the inlay/onlay technique.

The present study measured the diametral compressive strength, flexural strength, and modulus of elasticity of composite resins used in inlay/onlay systems. The effect of additional curing also was determined. SR-Isosit material had the highest diametral compressive strength, and SR-Isosit-Dentin material had the lowest flexural strength. The SR-Isosit composite resins had lowest elastic modulus and Estilux posterior C VS resin the highest. A negative correlation was found between diametral compressive strength and elastic modulus of the materials. It was concluded that the additional curing of Brilliant resin did not result in improved mechanical properties. For Estilux resin, additional curing increased flexural strength and modulus of elasticity.