Influence of Tooth Brushing on Surface Roughness of Pressable Ceramics

Objective: The aim of the study is to measure surface roughness of different pressed ceramics, which were glazed or polished, before and after artificial aging. Methods: 16 discs (diameter 10 mm, thickness 2 mm) were fabricated for 3 different pressed ceramics: Emax Press, Emax ZirPress, and Noritake CZR Press. Half of the specimens were glazed and the other half was polished with Dialite ceramic polishing wheels. Half of each group was artificially aged by 20,000 thermal cycles (5^oC and 55^oC in distilled water). One half of each specimen was protected with an adhesive tape, whereas the unprotected side was subjected to 20,000 tooth brushing cycles (200g/brushing stroke of 20mm). After brushing, root-mean-square (RMS) roughness was measured by confocal laser scanning microscopy. Statistical analysis was performed using ANOVA at p=0.05.

Results: (RMS/SD in nm) Different letters indicate significant difference

Conclusions: Tooth brushing does not increase surface roughness of pressed ceramics. Emax Press and Emax Zirpress mean roughness is not affected by glazing or polishing. Polishing of Noritake CRZ Press increases surface roughness significantly compared to glazing.