Paper Title
Mechanical Properties of Composites Materials Reinforced in Ceramic Particles

Abstract
The complete dentures are made from different acrylic resins by various technologies. These materials are fragile and frequently appear cracks that lead to fractures of prosthetic dentures. Many studies are done to develop the properties of PMMA resin that is used for upper and lower complete denture base materials, by using composite materials consists of poly methyl methacrylate (PMMA) resin as reference material, reinforcement with different weight fractions of ZrO2 particles (1%, 3%, 5%,7%) wt%. Acrylic resin (PMMA) and composite materials were prepared by Hand lay-up molding and investigated. The investigated the mechanical properties were hardness, tensile properties (ultimate tensile strength (UTS), elongation at break), impact properties (impact strength, fracture toughness), and flexural strength& shear stress. The resulting composites of mechanical properties, composite materials with (Acrylic +7% ZrO2) has the maximum hardness of (72.4) shore D, The ultimate tensile strength of 33.75MPa was obtained for (Acrylic +7% ZrO2), while the elongation at break decreases with increase in filler concentration of 5 % was obtained for (Acrylic +7% ZrO2) is lower than other composites . The highest impact strength with (Acrylic +3% ZrO2) (83 J/m2) than with other composites. The fracture toughness of the composites increases with increase in the ZrO2 has the maximum value 1.998 MPa.m-1/2. Flexural strength & shear stress of the composite materials increased with increasing of the weight fraction of ZrO2 particles at 7wt % (81)Mpa &(1.8)Mpa respectively . Index Terms- Acrylic resin, Zirconium Oxide, , mechanical properties.