金・白金2元合金の歯科インプラント材としての応用可能性の検討

抄録

Metals and ceramics e.g., stainless steel, titanium (Ti) or its alloys, aluminium oxide, hydroxyapatite, and so on have been used as biomaterials in the fields of oral surgery and orthopedics. Many studies for their biocompatibility and clinical usage have evaluated their merits or demerits. The present study has focussed actention on an evaluation of precious metals, especially gold (Au) and platinum (Pt) for dental implants.
Materials: Au-Pt alloys (Au weight %: 5, 20, 30, 40, 50, 60, 70, 80, 90, 95), Au (99. 99%) and Pt (99. 99%) were examined, and Ti (99. 5%) as a control. Methods: 1. Hardness test of Au-Pt alloy (Hv). 2. Cytotoxicity test used cultured cells. 3. Quantification of dissolved Au and Pt ions. 4. In vivo study used dogs for histopathology and immunohistochemistry. Results: From the point of mechanical function, Au-Pt alloys (5-80 Au weight %) suggested that they could be used as dental implants. Cytotoxicity of the Au-Pt alloy and Ti was no problem. Dissolved Au, Pt and Ti ions disappeared (<0.01 ppm). The Au-Pt alloys indicated excellent biocompatibility as well as Ti as materials for dental implants.