In vitro Study on the Impact Wear Behavior of Human Teeth

Impact wear behavior of human teeth against SiC ceramic was investigated using a specially designed impact test machine. Tests running up to 5 000,50 000,250 000,550 000,800 000 and 1 000 000 cycles were conducted, respectively. The worn surfaces of human tooth specimens were studied by means of various microscope examinations. The results show that the wear volume of human teeth increased nonlinearly with the number of impact cycles. Tooth surface damage was mainly characterized with slight plastic deformation at the early stage of impact wear. With the increasing number of impact cycles, delamination occurred on the worn surface, and then the depth of wear scar increased rapidly. As the wear proceeded, the tooth surface was gradually covered with a wear particle layer, and the wear rate decreased. In addition, the surface hardness of wear scar was found to increase with the number of impact cycles during the wear process.