Thesis & Dissertations

Purpose: to compare the color stability and fracture strength of two hybrid ceramic (Suprinity and Enamic) veneers versus Lithium Disilicate ceramic (IPS Empress II) veneers. Materials and methods: thirty freshly extracted maxillary central incisors were divided equally into three groups (n=10): group Em (IPS empress II, Ivoclar Vivadent) as a control, group VS (Suprinity, Vita Zahnfabrik), and group VE (Enamic, Vita Zahnfabrik). In incisal reduction of 1.5 mm was made with a butt joint margin and 0.6 mm finish line was prepared on the labial surface of each specimen and on the middle of the proximal surfaces. Each group received different type of veneers according to the sample grouping. Using spectrophotometer (Nippon Densmoku industries), ΔE was recorded for each specimen before and after 15 days of immersion in a coffee solution considering the value of ΔE= 3.3 as clinically significant staining threshold. All the specimens were subjected to fracture strength test using universal testing machine (The Testometric Company Limited) using cross head speed 0.5 mm/min at 135 degrees’ angle. One-way ANOVA and chi-square were used for statistical analysis. Results: regarding the mean color stability between studied groups, group VS scored the least ΔE (3.52±2.46) followed by group VE (4.14±1.94) then group Em (4.49±2.45). On the other hand, group VS scored the highest fracture strength values (471.04±274.5) followed by group Em (442.13±236.1) then group VE (394.72±160.84). One-way ANOVA revealed no significant differences between groups in both color stability (P=0.636) and fracture strength (P=605). Conclusion: the tested hybrid ceramics could present an acceptable treatment option for fabricating ceramic veneers. Keywords: hybrid ceramic, Lithium Disilicate, monolith, veneer, color stability, fracture strength.