Wear damage of human tooth enamel under simulated impact-sliding wear

This study investigates the mechanism of wear damage of human tooth enamel by applying reciprocating impact-sliding wear tests. Two sliding loads (20N, 49N) were applied. In general, greater the load, greater the wear damage. The wear tracks could be divided into the impact part and the sliding part, and the wear characteristics of enamel were different between two parts. Impact wear in the impact part displayed plastic deformation, quasi-plastic deformation and brittle fracture. Sliding part with abrasive wear exhibited microscale cutting and plowing processes. The impact motion was the main cause for the loss of enamel in the early stage which led to higher wear rate and a larger enamel loss. The sliding movement was the main reason for the loss of enamel in the later stage of the experiment which led to a steady wear rate and moderate material loss. • The vertical load plays a role in the cycle-dependent wear behavior of enamel under the impact-sliding motion. • Impact wear is the main mechanism for the impact part. • Abrasive wear was responsible for the sliding part. • The impact part displayed plastic deformation, quasi-plastic deformation and brittle fracture. • The sliding part exhibited microscale cutting and plowing processes.