STUDYING THE FLEXURAL PROPERTIES AND MAX.SHEAR STRESS OF SELF CURE PMMA RESIN FOR DENTURE APPLICATIONS .

Abstract

Poly Methyl Methacrylate were widely accepted material in dental and medical field due to the excellent biocompatibility and easy fabrication, however exhibit inferior mechanical properties. Therefore, the present study conducted to determine the flexural properties of PMMA based material by reinforcing PMMA with two different natural fibers (bamboo & siwak fibers). Discontinuous random fibers used in three lengths (2, 6 & 12 mm) and three weight percentage (3, 6 & 9 wt. %) of the both types of fibers. Results indicated that Flexural modulus, flexural strength and max.shear stress increase with increasing weight fraction and fiber length of fibers (bamboo & siwak) and reach the maximum amount at addition of weight fraction of (9 wt.%) and (12mm) length of fibers. The highest value of flexural modulus, flexural strength and max.shear stress were (10.09GPa), (112MPa), (6MPa) respectively, for composite specimens with bamboo fibers, while for composite specimen with siwak fibers (9.71GPa),(101MPa),(4.44MPa) at the optimum condition of (9wt.%) and (12mm) length . All composite specimens reinforced with bamboo fibers showed the highest flexural strength and flexural modulus among the composite specimen reinforced by siwak fibers.