Wang J.,Qingdao University |
Wang M.-Z.,Stomatological Hospital of Qingdao City |
Wang W.-C.,Stomatological Hospital of Qingdao City |
Yang M.,Stomatological Hospital of Qingdao City
Chinese Journal of Tissue Engineering Research | Year: 2013
Background: Zirconia ceramics is a novel oral repair material in recent years, and it has welcomed by patients because of its aesthetics and biocompatibility, but the research on the wearing ability of zirconia ceramics on the jaw natural tooth is rare. Objective: To observe the volume loss of zirconia ceramics and other four kinds of clinical commonly used full crown repair materials when grinding with steatite, and to compare with the natural tooth in order to research the wearing ability of zirconia and other repairing materials. Methods: The zirconia ceramic, vita ceramics, gold-palladium alloy, nickel-chromium alloy, cobalt-chromium alloy and fresh natural enamel in the control group were installed in the upper fixture of wear machine respectively, and the steatite porcelain was installed in the lower fixture. Load abrasion tests were performed in artificial saliva environment, and then the volume loss of the materials in the upper and lower fixture was calculated; the hardness of the materials above was tested with fiber hardness testing machine; the specimen surface abrasion morphology was observed under scanning electron microscope. Results and Conclusion: The volume loss of the five materials when grinding with steatite was larger than that of the fresh natural enamel in the control group (P < 0.05); the hardness of zirconia ceramics was highest, and the volume loss of zirconia ceramics when grinding with steatite was largest. The gold-palladium alloy had the smallest hardness, and the volume loss of gold-palladium alloy when grinding with steatite was similar to that of the natural teeth; the hardness of all the materials was positively correlated with the volume loss of grinding steatite porcelain (P < 0.05). The zirconia ceramic and vita ceramic were mainly performed as abrasive wear, and the surface was in fissure protruding-like structure with deep abrasion furrows and irregular morphology, the scattered pore structure could be seen on the abrasion surface. The abrasion surface of cobalt-chromium alloy was relatively smooth with shallow abrasion furrows, and the scattered metal abrasive particles could be seen on the abrasion surface; deep and wide abrasion furrows and a large amount of metal abrasive particles could be seen on the abrasion surface of nickel-chromium alloy; abrasion furrows was evenly distributed on the abrasion surface of gold-palladium alloy, and the exfoliative plaque could be seen occasionally with metal abrasive particles in it. The results indicate that zirconia ceramic is likely to cause excessive abrasion on the jaw natural tooth in clinical application, so polishing should be performed before permanent cements; the gold-palladium alloy has the best wearing ability which is close to that of the natural teeth, and it is considered the better posterior region full crown repair material; the hardness of the dental prosthetic material can not represent the wearing ability, the microstructure of the material surface and other factors should be considered when using in order to play the advantages of various materials.