A Study on the accuracy of the elecronic apex locator using a micro-computed tomography

미세단층촬영기(Micro-CT)를 이용한 전자 근관장 측정기의 정확성에 관한 연구

The length of root canal has to be measured to cure root canal. Several apex locators were developed to measure the length of root canal. And they were verified by X-ray or micrometer method. But these methods do not consider the non-linear bends of pulp and have ${\pm}0.5mm$ error which is large to measure the length of root canal. The purpose of this study is the research of new method to measure the length of root canal and verifying the apex locator using Micro-CT. The length of root canal of 6 teeth were measured with the apex locator. When the apex locator reads 0.5, 0.6, 0.7, 0.5, 0.9, 1.0mm, the teeth with the file fixed were photographed. The average lengths of root canal of 6 teeth measured by Micro-CT were 0.488, 0.589, 0.680, 0.775, 0.897, 0.992mm.