Study Of Using The Ni-Cr Alloy Post And Increasing Cement Strength(Zinc Polycarboxylate) On The Stress Distribution Of Restored Human Tooth

الملخص

The effects of stress on dental restoration and upon teeth themselves have been a topic of interest to dental researchers for the past twenty years. A model of a maxillary central incisor (front tooth) restored with titanium alloy post and another post nickel alloy in combination with different cements, are established. The stress in dentin, posts, cores and crowns have been evaluated and compared with two different post materials and two different cements. The research is performed theoretically , numerically and experimentally, A composite beam formula is derived for analysis and the stress at sections through the tooth. The numerical analysis is achieved by use of ANSYS/ver.11 software. The material of tooth is assumed to be isotropic, homogeneous and elastic. A load of 100 N is applied at an angle of 45۫ to the longitudinal axis at the palatal surface of the crown. The mechanical properties and chemical composition of nickel alloy and Zinc polycarboxylate are measured experimentally. In this study , There are three model type (I,II and III) , model I including the standards restoring tooth (Titanium post tooth ), model II including new post (Ni-Cr) alloys and third model by using the high strength cement(Zinc polycarboxylate) .