鎳鈦旋轉器械應用於根管切削之 力學行為分析

Mechanics of Nickel-Titanium Rotary Instrumentation Applied to Endodontic Treatment

黃世明(Shi-Ming Huang)

指導教授 ： 陳文斌

中原大學/工學院/醫學工程研究所/碩士(2006年)

https://doi.org/10.6840/cycu200600661

摘要

中文摘要
傳統手動式根管銼之清創方式，雖然可得到較令人滿意的清創效果，卻較耗時且需要較純熟的技巧。然而，在匆促或不熟練的操作下，更常導致人為造成的根管移位、變形、穿通，甚至器械斷裂等危險。而近幾年來，鎳鈦合金器械的廣泛應用不但增加了器械的彈性，且在許多學者的研究中，亦證實鎳鈦旋轉器械更能減少在彎曲根管修形的過程中所容易造成的副作用等困擾。但是，鎳鈦旋轉器械卻有著無預期斷裂的風險。因此，本研究將利用有限元素法探討鎳鈦旋轉器械斷裂的影響因子。希望能對如何防止鎳鈦旋轉器械的斷裂以及降低其斷裂風險之評估，進而設計出製備根管最佳化的流程以及對於器械創新的設計提出建議。首先，利用器械於根管製備過程切削的體積量分析，發現ProTaper每一支器械其主要的切削工作區間。然後，利用此結果作為設計新器械的依據，進而設計出一組新型器械。新型器械的設計概念為分段切削，改變切削螺紋的工作區間，將不需要參與切削的位置設計為無螺紋平滑曲線。其可使器械降低摩擦力及避免過度切削情形發生。最後，將新型器械與ProTaper做力學行為分析比較，結果顯示新型器械於根管內之應力較小、器械彎曲斷裂風險評估較低以及製備一完整根管效率提高。

關鍵字

斷裂風險評估 ； 鎳鈦旋轉器械 ； 有限元素法 ； 鎳鈦合金

並列摘要

Abstract
Using the traditional Endodontic hand files to prepare root canal, though it can achieve more satisfactory cleaning and shaping, but more consuming time and need more skillful technique. However, inexperienced in operation usually cause the transportation, zipping, perforation and separation. In recent years, the Nickel-Titanium (Ni-Ti) alloy instruments have been used widespread, they have the advantages of the higher elasticity and a lot of researchers have also verified few complications during canal preparation. However, separation is still a concern with Ni-Ti rotary instruments and they have the risk of unexpected fractures. So, the purpose of this study was to investigate the fracture influence factor of Ni-Ti rotary instruments by using finite element analysis. Then lead to recommendations for preventing instrument separation and reduce its fracture risk. The analysis results can be used to estimate optimization prepare procedure and to provide suggestions for the instruments innovative designs. First, we used the cutting volume of root canal preparation to find ProTaper files major cutting region. The new-type instruments have been designed according to this result. The design concept of the new-type files is the cutting by stage and the alteration major cutting region. They don’t use region have been designed smooth curve, in order to reduce frictional force and avoid cutting excessively of Ni-Ti rotary instruments. Finally, we compared the mechanical behaviors of new-type files and ProTaper files, the results showed the new-type files have low stress in the root canal, the risk of fracture have been decreased and more efficiency of root canal preparation.

並列關鍵字

Risk of fracture ； Nickel-Titanium alloy ； Ni-Ti rotary instrument ； Finite element method

參考文獻

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