- 學位論文
牙科鎳鈦旋轉器械疲勞斷裂之監測
Monitoring Fatigue Fracture of Dental Ni-Ti Rotary Instruments.
摘要
鎳鈦旋轉器械(Ni-Ti rotary instrument)近年被牙醫大量應用在根管治療，臨床上需將鎳鈦旋轉器械深入牙髓腔內以清潔內部達到治療功效。鎳鈦旋轉器械在牙髓腔內持續旋轉使用會因交替的張應力(tension)和壓應力(compression)作用導致無預警疲勞斷裂的發生，若斷在牙髓腔內更會增加治療難度以及造成不必要的醫療糾紛。要在裂縫出現後但斷裂發生前加以偵測，前人的作法為藉由暫停方式對鎳鈦旋轉器械做靜態之裂縫成長或疲勞斷裂之量測，此法無法提供一個連續時間且全自動量測系統，故在臨床上無實際用途。 本研究是在探討兩個品牌分別為Protaper F2與Endo Wave之鎳鈦旋轉器械在不同的曲率半徑、曲率角度以及轉速下，在連續彎曲旋轉中產生的聲音以及因切削磨刮所產生的振動波變化。本研究將布拉格光纖光柵(Fiber Bragg Grating, FBG)黏貼於與鎳鈦旋轉器械接觸發生磨刮作用的金屬塊上以及並非直接與鎳鈦旋轉器械接觸發生磨刮之馬達上感測振動，以及使用麥克風感測聲音，做動態疲勞破壞監測，並從時域及頻域比較後希望能在鎳鈦旋轉器械產生裂縫但在斷裂前能夠即時提供預警。 不論是麥克風或是雷射泵激光源雙FBG光路感測器，在單獨或者搭配使用下，皆有達到提出具有物理意義的預警和延長使用時間並節省醫療資源等方面的例子出現。 關鍵字：牙科根管治療、鎳鈦旋轉器械、疲勞破壞監測、布拉格光纖光柵。
並列摘要
In recent years, Ni-Ti rotary instruments are widely used in dental root canal treatment, the dentist will let Ni-Ti rotary instruments continued to rotate and in-depth dental root canal to clean the inside of therapeutic efficacy. Ni-Ti rotary instruments used in the dental pulp will cause fatigue fracture without warning due to continued rotation of alternating tensile stress and compressive stress. If Ni-Ti rotary instruments fracture in the tooth root canal, it will increase the difficulty of the treatment and also cause some unnecessary medical disputes. Some researcher conduct static measure of crack growth or fatigue fracture by way of stopping the rotation, but this method can’t provide a continuous-time and automatic measurement system, we can not use it in clinical. This study proposed to investigate the sound from successive bending rotation and the variation of the vibration wave resulting from the scratch of cutting, with two brands of Ni-Ti rotary instruments which are Protaper F2 and Endo Wave under different radii of curvature, curvature angle and rotational speed. In this study, the sensing of sound is performed by the microphone and the sensing of the vibration wave is performed by two FBG (Fiber Bragg Grating) which are affixed to the metal block and the motor. The sensors can be used to monitor the dynamic fatigue fracture, and in comparison with time domain and frequency domain, hoping to foreknow and warn before the fracture of Ni-Ti rotary instruments. Whether the microphone or the two FBG optical pathes of laser pump light source which are used separately or simultaneously, there are some examples which reach the achievements of supplying the physical meaning of warning, prolonging the operating time, and saving the medical resources. Keywords: Dental root canal treatment, Ni-Ti rotary instruments, Fatigue fracture monitoring, Fiber Bragg Grating.