Wear resistance and surface roughness of two types of monolithic glass ceramics: An in vitro study

Aim: The purpose of study was to evaluate wear and surface roughness of ZLS compared to lithium disilicate glass ceramic before and after simulated mastication. Materials and Methods: Thirty samples were divided according to material of construction into three groups (n = 10). Group (1): E Max-CAD, Group (2): Celtra duo ZLS, Group (3): Celtra press ZLS. The sectioned samples of E-max CAD blocks were polished and crystalized. The sectioned samples of Celtra Duo ZLS blocks were glazed and fired. The Ingots of celtra press were lab pressed, sectioned, glazed and power fired. The two-body wear testing was done using chewing simulator. Each ceramic sample was weighed and evaluated for surface roughness before and after wear simulation test using electronic analytical balance and the optical profilometry, respectively. Results: IPS E-max CAD revealed highest amount of weight loss with no statistically significant difference between groups. The change in weight for each group was non-significant . The roughness mean value for E-max CAD was significantly decreased and recorded the lowest roughness change. No significant difference in the roughness mean value between the two celtra materials. The roughness change for either Celtra Duo or Celtra Press groups was non-significantly increased. Conclusions: ZLS Celtra ceramics had insignificant less wear and significant higher surface roughness with enamel antagonist compared to E-max CAD. Although wear and roughness were affected by the surface finishing of glass ceramics, the construction method of ZLS restorative materials had no significant impact on both.