Effect of In-Office Bleaching Techniques and Topical Fluoride Application on Color and Surface Roughness of Two Types of Dental Ceramics (In-Vitro Study)

Abstract

Objective: The purpose of this in-Vitro study was to assess the effect of two different bleaching techniques and topical fluoride application on the color and surface roughness of two types of CAD/CAM dental ceramics. Materials and methods: In this study 40 discs of two types of CAD/CAM dental ceramics were used {Lithium disilicate glass ceramic (IPS e.max CAD) (Group E) and Zirconia-reinforced lithium silicate ceramic (Vita Suprinity) (Group S)}. Baseline measurements for color and surface roughness (Ra) were taken using spectrophotometer and Atomic Force Microscope respectively. The specimens of each ceramic material were randomly divided into two subgroups (n=10) according to the bleaching agent used: a photo-activated Zoom bleaching agent (Z) and a chemically-activated Opalescence Boost 40% agent (O). Two measurements of color and surface roughness were done: immediately after bleaching application (Immediate I) and after one week from the last bleaching session (Delayed D). Then each specimen from each ceramic material was exposed to Acidulated Phosphate Fluoride (APF) application and final measurements of color and surface roughness values were done. The obtained data were collected, tabulated and statistically analyzed. Results: The results showed that, bleaching had a statistically significant effect on mean color change ∆E of the tested ceramic materials in all tested conditions (I, D &F). No significant difference on mean ∆E of the two ceramic materials. The Opalescence Boost 40% showed higher statistically significant difference in color parameters than the Zoom agent. Vita Suprinity showed higher statistical significant difference in color parameters than E.max CAD. Moreover, ceramic type and bleaching agents had a statistically significant effect on mean Ra. In immediate bleaching, the Vita Suprinity bleached with Zoom gel (SZ) showed the highest mean Ra value while in delayed bleaching and after fluoride treatments, E.max CAD bleached with Opalescence agent (EO) showed the highest mean Ra value. After fluoride treatment, the mean Ra of the tested ceramic materials demonstrated higher values than bleaching only. In addition, there was a positive correlation between color parameters and surface roughness. (1244) Fatma M. Soliman, et al.