义齿用Ti-6Al-7Nb合金铸件挠度的研究

Transverse deflection study of casted Ti-6Al-7Nb alloy for dental clinic use

目的:通过对相同长度、宽度、不同厚度的Ti-6Al-7Nb合金铸件挠度的测量,观察铸件厚度与挠度的关系,为确定Ti-6Al-7Nb合金铸造义齿基托的适合厚度提供实验依据。方法:参照ISO关于义齿基托材料挠度的标准,测量不同厚度Ti-6Al-7Nb合金铸件的挠度,并与纯钛、Ti-6Al-4V合金及Co-Cr合金对比。结果:Ti-6Al-7Nb合金、纯钛及Ti-6Al-4V合金铸件的厚度在0.65mm时可以达到义齿基托挠度的标准;Co-Cr合金在0.57mm时可达到标准要求。结论:在临床制作Ti-6Al-7Nb合金义齿基托时,厚度应不低于0.65mm。

Objective The aim of this study was to obtain the reasonable thickness of Ti-6Al-7Nb alloy used for denture base material. Methods According to the standard of ISO, the transverse deflection tests of Ti-6Al-7Nb alloy after casting were performed. Pure titanium, Ti-6Al-4V alloy and Co-Cr alloy were examined as the control. These groups of wax patterns with different thickness were designed. Ti-6Al-7Nb alloy,pure titanium and Ti-6Al- 4V alloy were casted into molds at 300℃,which were made of zircon investment, using a casting machine（China）. With a program of vacuum,pressure and centifuge casting.Co-Cr alloy was casted by normal method in clinical. The transverse deflections of these four alloys castings with three different thicknesses were measured using a transverse testing machine. Results When the thickness is 0.65 mm for Ti-6Al-7Nb alloy, pure titanium and Ti- 6Al-4V alloy, and 0.57 mm for Co-Cr alloy, the transverse deflections could satisfy the requirement. Conclusion The transverse deflection is one of the key indexes for evaluating the ability of dental material to bear biting forces.The reasonable thickness of Ti-6Al-7Nb alloy used as denture base material is 0.65mm.