Abstract

AN EVALUATION OF THE EFFECT OF ARTIFICIAL SALIVA WITH DIFFERENT PH ON SHEAR BOND STRENGTH OF VENEERING CERAMIC TO METAL AND ZIRCONIA SUBSTRUCTURE (IN VITRO STUDY)

Inas Mohammed and Dr. Zahraa Nazar Alwahab*

Abstract

Background: For the past 40 years the porcelain- fused- to metal system has been extensively used in fixed partial denture (FPDs) and still represents the gold standard. Bilayering concept was first adopted by metal ceramic restoration which involves the fabrication of high strength framework layered by a high esthetic veneering material. Zirconia framework substituted metal as a framework material in all ceramic restoration, due to it high exceptional mechanical properties. Objective: To evaluate the effects of artificial saliva with different PH values neutral (7.0), acidic (3.5) and alkaline (10.0) on shear bond strengths of veneering ceramic to metal and zirconia substructures. Material and method: Sixty rectangular shape samples were fabricated from metal and zirconia, have dimensions (9mm length ×4mm width × 4mm height), the surfaces of the rectangular samples (4mm × 4mm) were veneered with corresponding ceramic according to manufacturer's instructions. Final thickness of veneered ceramic was 3mm. An artificial saliva solution was prepared with 3 different pH values (7, 3.5,10) and the 60 samples of zirconia and metal were divided randomly into 3 solutions with 10 specimens per each group for 21 days in incubator. Results: the highest mean value for both zirconia and metal core was for neutral artificial saliva followed by alkaline and acid. ONE – way ANOVA test and LSD showed a high significant differences among all groups.

Keywords: Shear Bond Strength, Zirconia, Artificial Saliva, Metal Ceramic.