In Vitro Study on Dental Abrasive Finishing of Restorative Ceramics using Diamond Burs in Dental Surgery

摘要

With the aesthetics' enhancement, there is a growing demand for the use of restorative ceramics in dental surgery. However, ceramic materials are hard and brittle, and problems such as surface damage, crack, and fatigue were easily produced in dental abrasive finishing. Consequently, these flaws could cause the strength decrease of the ceramic, which manifest the shortage of the lifespan in dental. Contraposing these problems, a high-speed handpiece with diamond burs was used when finishing the leucite glass ceramic in the dental surgery. In this paper, finishing force, specific energy and surface integrity including the roughness and morphology were observed. The results revealed that both normal and tangential forces increased with the increasing of feed rate and depth of cut, while there is an apparent decrease of the specific energy. These two parameters were bigger in the up finishing than that of down finishing. Finishing parameters have little effect on surface roughness, according to the observation of a scanning electron microscope. It is easily found that the finished surface was consisting of brittle fracture and plastic deformation. For comprehensive, good surface quality could be obtained in the down cutting other than up cutting.