Akademik Veri Yönetim Sistemi
ACTA ODONTOLOGICA SCANDINAVICA, cilt.73, sa.7, ss.503-507, 2015 (SCI-Expanded)
Objective. The aim of this study was to evaluate the micro-mechanical properties of a light-cured resin cement in four different shades when polymerized through a leucite-reinforced glass-ceramic in different shades and thicknesses. Materials and methods. A light-cured resin cement in four different shades (HV+ 1, HV+ 3, LV-1 and LV-3) was selected for this study. The specimens were cured by using a LED-unit (Bluephase (R), IvoclarVivadent) for 20 s under a leucite-reinforced glass-ceramic (IPS Empress (R) CAD, IvoclarVivadent) in two different shades (A1 and A3) of different thicknesses (1 and 2 mm). Specimens cured directly, without an intermediate ceramic, served as control. The specimens were stored after curing for 24 h at 37 degrees C by maintaining moisture conditions with distilled water. Micro-mechanical properties (indentation modulus, E; Hardness, HV; creep, Cr) of the resin cements were measured with an automatic microhardness indenter (Fisherscope H100C, Germany). Twenty groups were included (n = 3), while 10 measurements were performed on each specimen. Data were statistically analyzed by using one-way ANOVA and Tukey's post-hoc test, as well as a multivariate analysis to test the influence of the study parameters. Results. Significant differences were observed between the micromechanical properties of the tested resin cements (p < 0.05). The resin cement shade showed the highest effect on the micromechanical properties (Partial-eta squared (eta(2)(P))-E = 0.45, eta(2)(P)-HV = 0.59, eta(2)(P)-Cr = 0.29) of the resin cement, followed by ceramic thickness (eta(2)(P)-E = 0.38, eta(2)(P)-HV = 0.3, eta(2)(P)-Cr = 0.04) and ceramic shade (eta(2)(P)-E = 0.2, eta(2)(P)-HV = 0.26). Conclusions. Resin cement shade is an important factor influencing the mechanical properties of the material. Light shades of a resin cement express higher E and HV as well as lower Cr values compared with the darker ones.