Experimental Study Of The Friction And Wear Properties Of Six Restorative Materials And Natural Tooth Enamel

Objective: The purpose of this study was to evaluate and compare the wear of six kinds of dental materials that was widely used clinically. The wear mechanisms were discussed to provide experental reference for selecting proper restorative material to protect opposite natural enamel of patient.Methods: 1). Experimental groups: Pure Ti, Ti alloy, Au-Pd alloy, Ni-Cr alloy, AgHg alloy, ceramic were fabricated into thirty uniform 8.0x8.0x2.0mm~3 block. Five specimens in each group.2).Control group: Five recently extracted mandibular third molar of adults were fabricated into 8.0 x 8.0x 2.0mm~3 block. 3). Steatites were fabricated into discs in the diameter of 25.0mm and thickness of 2.0mm to act as counter sample materials. 4). The mass loss of each specimen and the opposing steatite were weighted by electric balance. 5). The volume loss of the materials and opposing steatites were analyzed by SPSS11.5 and the difference was compared.Results: 1. The volume loss of specimens from group A to group G was: The ranking of the volume loss of six materials and enamel from the most to the least was: group A, group E, group C, group D, group B, group F, group G. The significant difference was found between group A and the other groups (P<0.01) . No significance was found between group Gand F. The coefficient of friction of A-G: 0.68, 0.11, 0.09, 0.41, 0.38, 0.48, 0.65 respectively.Conclusions: 1). The six materials were less resistant to wear thannatural tooth. The wear of pure Ti, AgHg alloy and Ni-Cr alloy are the most and the ceramic is the least. 2). Six materials all created abrasion to enamel and Au-Pd alloy created the least friction to enamel. 3). The coefficient of friction of Au-Pd alloy and AgHg alloy proves that both of them are not suited to be the material to recover the occlusal surface...