鈦金屬牙科植體表面氧化層對齒槽骨應力影響之有限元素分析

Abstract

鈦金屬的機械性質，較其它金屬具有低密度及較高機械強度的優點。此外，鈦金屬本身的化學性質較穩定，對環境的抗腐蝕性佳。因此，鈦金屬普遍應用於生醫材料上，如牙科植體。 然而不可忽視的是，當鈦基金屬植入人體中，仍會有少量離子釋出；儘管鈦金屬的剛性與齒槽骨的剛性相近，但仍比齒槽骨中的皮質骨大了六倍，差異仍然很大；而一個適當的緩衝層，可以降低植體與齒槽骨間的強度差異；基於這些觀念，植體表面改質成了一個很重要的研究項目。 本研究主要目的，在於利用有限元素法，分析鈦植體表面鍍上不同厚度及孔隙率的氧化層後，探討其對於齒槽骨的應力影響，以提供後續植體設計參考。

Titanium has lower density and better strength/weight than most steels. Besides, titanium is chemically more stable, it can resist corrosion in many hostile environment. Thus, applications of the titanium in medical uses, such as dental implant, are very common. However, titanium releases ions when it was embedded in human body. In the dental implant application, although the titanium stiffness is close to alveolus bone, it is still six times higher than cortical bone, the strength difference between these two materials is too large. An isolation layer between the titanium implant and the cortical bone will help reduce difference in strength. Based on this concept, the modification of implant surface is an important subject in the application of dental implant. In this study, the finite element method was used to analyze titanium implants, the implant has nano-porous of oxide layer on the surface. Stress distribution on the implants and alveolus bones were investigated. And the results can provide important information for the design of the implant.