Comparison the Surface Roughness of Polishing And Glazed Ceramic With Glazed Zirconium Based Ceramic

Abstract

Porcelain veneer restoration often require modification at laboratory and chair side prior to cementation .Common adjust - ments include contour, occlusion , color correction , and special characterization masking of imperfections and final glazing. The purpose of this study to compare surface roughness of polished, glazed porcelain with ceramic based zirconium. Thirty samples {Twenty porcelain specimens resembling flat-back facing (Metal porcelain buttons) of vita ceramic and ten specimens of ceramic based zirconium } were fabricated according to the manufacturer’s Instructions.(prepared with dimension of (10mm) in diameter and (2mm) in thickness). The specimens were divided into three groups according to the type of surface treatment tested .Each group consisted of ten specimens and the groups were distributed as follows:- - Group A: Polished unglazed porcelain with Rubber wheel. - Group B: Glazed ceramic based Metal. - Group C: Glazed ceramic based with zirconium. The surface roughness evaluation of the specimens was carried out by a surface roughness analyzer device (profilometer). Statistical analysis of data using (ANOVA- one way test) indicated high significant differences among the tested groups. The highest roughness value was scored by group A (porcelain polished with rubber wheel ) followed by group B ( glazed ceramic based Metal.) then group C ( glazed ceramic based zirconium). - Group (A) showed statistical significance in comparism to group (B). - Group (A) showed high statistical significance in comparism to group(C) -Group (B) showed statistical significance in comparism to group(C). According to the conditions under which this study was carried out, it may be concluded that mechanical finishing, polishing procedures were not able to provided a surface as smooth as the glazed surface for the tested porcelain.