The Investigation Of The Wear Resistance Of Machinable Ceramic Vita Mark â…¡

Purpose: The investigation of the wear resistance of machinable ceramic Vita Mark II was to consider weather the machinable ceramic Vita Mark II was suitable to clinic through comparing the wear resistance of machinable ceramic Vita Mark II with other traditional porcelains and natural dentition. Methods: Two-body wear testing was used to compare the wear resistance of machinable ceramic Vita Mark II and other traditional porcelains. After wear testing, the surface hardness, surface roughness were determined, The volume loss, hardness and roughness values were subjected to analysis of variance, One-way ANOVA and Post Hoc Test's to determine significant differences. Scanning electron photomicrographs were made using representative ceramic form each group, ceramic analysised respectively, and analysised the reasons. Results:1. After wear testing, the volume loss of the machinable ceramic Vita Mark II was significantly less than other ceramics (p<0.05), but was significantly more than natural dentition (p<0.05 ) .2. The hardness of machinable ceramic Vita Mark II was compared with otherceramics, found no consistent significant difference (p>0.05) , compared with natural dentition , the machinable ceramic Vita Mark II ' hardness values was significantly higher (p<0.05) .3 . Compared with other ceramics , the surface roughness of Vita Mark II was significantly lower ( p<0.05 ) , but compared with Vita VMK 95, the surface roughness was no consistent significant differences (p>0.05). The four traditional porcelains' surface roughness were no consistent significant difference (p>0.05).4. From the SEM, we can determined that the density of machinable ceramic Vita Mark II was more steady, the pore was less and the crystals grain size was more uniformly than other traditional porcelains.Conclusions1. The machinable ceramic Vita Mark II was surpasses than traditional porcelains, it was able to use in clinic.2. The wear resistance of machinable ceramic Vita Mark II was inferior than natural dentition.