利用有限元素分析及田口方法探討根管治療後小臼齒之生物力學分析

Biomechanical analysis of endodontic treated premolar by integration of finite element method and Taguchi method

黃莉婷(Li-Ting Huang)

指導教授 ： 林鼎勝

義守大學/醫學院/生物醫學工程學系/碩士(2017年)

摘要

牙齒若因齲齒引起牙髓發炎或外傷導致牙齒失去部分結構缺失都需接受根管治療，雖然根柱已廣泛用於根管治療後牙齒，但整體牙齒復形設計參數間相互作用其生物力學行為影響並不明確。因此本研究將利用電腦輔助分析以及田口實驗設計方法，探討根柱材料(Gold alloy、Titanium、Fiber)、根柱直徑(1.2 mm、1.5 mm、1.8 mm)、根柱長度(7 mm、9 mm、11 mm)、環箍高度(0 mm、1 mm、2 mm)、牙冠材料(Gold alloy、Ni-Cr alloy、Ceramic)、齒槽骨降低高度(1.5 mm、3 mm)及牙周膜韌帶厚度(0.25 mm、0.5 mm、0.75 mm)之最佳參數設計以提供給臨床醫師作為治療參考。
結果顯示，對於剩餘齒質之應力有顯著影響之因子為齒槽骨降低高度及環箍高度；根柱之應力有顯著影響之因子則是根柱材料、根柱長度、環箍及齒槽骨降低高度。在齒槽骨高度下降會使剩餘齒質及根柱之應力上升，且隨著骨質流失剩餘齒質應力會往牙根部位移動。在環箍設計高度1 mm時剩餘齒質上能有效降低應力。增加根柱直徑及長度，可降低剩餘齒質上應力值。玻璃纖維根柱會使剩餘齒質之應力呈均勻分布，應會有降低垂直牙根斷裂之可能性。

關鍵字

根管治療 ； 根柱 ； 環箍 ； 有限元素分析 ； 田口方法

並列摘要

Endodontic treatment is necessary when the tooth is infected due to severe caries or traumatic damages of tooth structure. To prevent the tooth fracture, which was caused by excessive occlusal force, after endodontic treatment, post-core system is commonly used for the recovery of occlusal function and the retention of the restoration. However, the biomechanical interaction of the design parameters was not clear. The objective of this study is to investigate the biomechanics of endodontic treated premolar by integration of finite element method and Taguchi method. The optimal design parameters of preparation for tooth restoration, including post material, post diameter, post length, ferrule height, crown material, alveolar bone loss and the thickness of periodontal ligament, was determined. The result indicated that alveolar bone and ferrule height have significant effect on dentin stress. In addition, post material, post length, ferrule height and alveolar bone have significant difference for post stress. Dentin and post stresses would increase with the reducing height of alveolar bone. Dentin stress would reduce when the ferrule height was 1mm and the post diameter and post length increased. Fiber post showed homogeneous stress distributions in surrounding dentin and would reduce the possibility of root fracture.

並列關鍵字

Endodontic ； Post ； Ferrule ； Finite element method ； Taguchi method

參考文獻

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