Dynamic and static moduli of elasticity of resin-based materials

Objectives: The purpose of this study was to assess and compare the elastic moduli of 34 resin-based materials using a dynamic and a static method. The effect of water storage was also studied up to 6 months. Methods: Five samples of each material were prepared according to ISO-4049. The dynamic moduli were first determined non-destructively from the fundamental period of the vibrating specimen, then the static moduli were determined by a three-point bending test. The percentages of fillers by weight were determined by ashing in air at 900°C. Results: Low values were obtained with flowable composites as well as with two packable resin composites. Correlations were found between the static and the dynamic modulus of elasticity ( r=0.94; p=0.0001) as well as between the weight percentage of fillers and the moduli of elasticity ( r=0.82; p