Effect of Monolithic Zirconia vs. Gold Alloy on the Wear of Human Enamel: An in vitro study

Abstract

The purpose of this study was to evaluate the effect of monolithic zirconia vs. gold alloy type IV on the wear of human enamel under different occlusal loads. Materials and Methods: Forty square plate specimens, 6×6×2 mm, were prepared from monolithic zirconia (Bruxzir, n=20) and type IV gold (Begostar, n=20) and divided into two groups. Forty freshly extracted premolar teeth for orthodontic purpose were sectioned mesio-distally and only the cusp tips of the buccal halves were used as antagonists in the testing procedures. All of the specimens were mounted to chewing simulator with the cusp antagonists, half of them were subjected to(50000 chewing cycles under 50N load), the other were subjected to (50000 chewing cycles under 150N load)cyclic loading (50 N load, 3700 cycles ). Data were submitted to two-way ANOVA, and statistical significance was set at p < 0.05. Results: Type IV gold alloy based restorations had significantly little wear effect on human enamel than that of monolithic zirconia (Bruxzir) based restorations in high load. However in low load it was non-significant.