Bond Strength of Porcelain to Titanium and Titanium Alloy, A Comparative Study with Conventional Metal-Ceramic Systems

In the past few years, the use of titanium in dentistry has noticeably increased because of its superior biocompatibility, corrosion resistance, desirable physical and mechanical properties, and low cost. The growing trend involves the use of titanium as an economical and biocompatible replacement for the existing alloys in prosthetic dentistry. Titanium metal’s affinity for gaseous element such as oxygen may affect the titanium-ceramic bond. Objectives: The purpose of this study was to evaluate the bonding potential between low fusing porcelain and pure titanium and titanium alloy, and to compare the bond strength with those of three conversional metal-ceramic systems. A 3-point bending test was used to evaluate bonding strength. Rematitan casting unit was used to cast the commercially pure titanium and titanium alloy specimens and Noritake low fusing porcelain was applied to them. The Gold-based, Palladium-based and the Ni-Cr alloys were melted and cast with an automatic centrifugal casting machine and Vita VMK 95 Conventional porcelain material was applied to them. The Instron testing machine was used to perform the bending test.

The mean bond strength values obtained with the five different metals were 35.60 MPa for the pure titanium, 14.63 MPa for the titanium alloy, 56.42 MPa for the Gold-based alloy, 62.07 MPa for the Palladium-based alloy and 55.88 MPa for the Ni-Cr alloy. There was no significant difference in the bond strength between Gold-based, Palladium-based and the Ni-Cr groups which exhibited significantly greater bond strengths compared to the titanium and titanium alloy groups (P<0.0001). Furthermore, the titanium group showed significantly greater bond strength than the titanium alloy group (P<0.0001).

The bond strength of the conventional metal-ceramic combination was significantly greater than the bond strengths of the cast pure titanium- titanium alloy-Noritake ceramic combinations. Titanium-Noritake ceramic system showed significantly higher bond strengths than titanium alloy-ceramic one.