應用有限元素分析植體套件上部不同高度下植牙系統的應力分佈

Stress distribution on dental implant systems by different height in upper part of Ti base: A finite element analysis

林融駿(Rong-Jun Lin)

指導教授 ： 燕敏 ； 湯正明

中山醫學大學/口腔醫學院/口腔材料科學研究所/碩士(2014年)

https://doi.org/10.6834/CSMU.2014.00096

摘要

目的：探討植體套件Ti base上部在不同高度下，進行實體及有限元素分析最大抗壓性質及疲勞測試，觀察植體內部的應力分佈狀況。材料與方法:實驗用實體試片由使用Ti-6Al-4V材料製作的植體套件Ti base、螺絲(Screw)和植體部(Implant)，以及使用氧化鋯材料製作支台(Abutment)所構成。實驗組試片之Ti base上部結構的高度分為 2、3、4 mm，對照組為5 mm。分別進行實體抗壓測試及疲勞測試。此外模擬前牙咬合情況，利用有限元素分析靜態抗壓及動態疲勞試驗，觀察植體套件及植體之間的應力分佈的情形與關係。結果:結果顯示實體試片當Ti base上部高度為2 mm時，植體產生的抗壓應力最大，對照組之試片產生的抗壓應力最小，這兩組比其他組有明顯的差異(p<0.05)。有限元素分析的結果表明在同樣咬合力的條件下，Ti base上部高度為2 mm時，分佈在植體套件與植體交接處的局部最大抗壓應力大於其他實驗組。隨Ti base上部高度的增加，在螺絲上產生的局部抗壓應力也會增加，應力分佈範圍擴大。疲勞試驗的結果T3組內負載最大抗壓力的10% ~ 80%能承受高週期疲勞的試片數量優於其他組別。在疲勞測試中，實驗組Ti base上部高度2 mm時，觀察應力明顯集中植體套件與植體交接處。結論：實體抗壓測試時，Ti base上部高度2 mm比高度5 mm能承受的最大壓應力大。有限元素靜態抗壓分析內，植體套件上部高度設計較短時，在植體套件下部壓縮區產生較大的壓應力，而對螺絲的應力作用較小。在有限元素分析下，疲勞試驗中各組試片在施加的力量為其最大負載力的10%時，皆可承受力的107次的反覆作用，每一組的疲勞限落於最大負載力的10% ~ 23%之間區域。

關鍵字

牙科植體 ； 有限元素分析 ； 植體套件 ； 應力分佈

並列摘要

Purpose: The study was to explore the effects of Titanium (Ti) base upper part at different heights on mechanical properties by compression tests and fatigue tests. The stress distributions inside the implants with various heights of Ti base were analyzed by finite element method.
Materials and Methods: The specimens were comprised of Ti base, screw and the implant body (made of Ti-6Al-4V), and Zirconia abutment. Specimens were grouped by the heights of their upper structure (2, 3, 4 and 5 mm) and the control group was 5 mm. Compression tests and fatigue tests were conducted. We used finite element analysis in static and dynamic compression fatigue test to observe the stress distribution within these implant kits.
Results: The results showed that specimens with 2 mm upper structure had the largest compressive strength and specimens in control group had the smallest compressive strength, significantly different from the other two groups (p < 0.05). Finite element analysis results showed that the maximum compressive stress of Ti base with 2 mm upper height distributed in the junction of implant and Ti is larger than those in other groups. The local compressive stress generated in the screw increased with increased height of Ti base. Specimens of Ti base with 3 mm performed the best in fatigue test compared to other groups.
Conclusion: The physical compression test, Ti base height of 2 mm upper group is greater than the height of 5 mm group can withstand the maximum compressive stress. Finite element analysis of static compression, the height of the upper part of the implant package design is short, compressing the implant package in the lower region have a greater compressive stress, and less stress on the screws. Fatigue test specimens in each group for which the maximum load is applied to the power of 10% strength, endurance can be repeated millions of times an action. In finite element analysis, compressive fatigue limit of each group was approximately 10 to 23% from their maximum compressive strength.

並列關鍵字

Dental implants ； Finite element analysis ； Ti base ； Stress distribution

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