The Research Of Simulated Canals By Micro-CT And Finite Element Method

Root canal therapy is a traditional treatment for pulpitis and periapical periodontitis. For several decades, there have been many kinds of modified techniques. Correspondingly, some indexes are used to evaluate these techniques.The subject is composed of two parts: firstly, we assess the preoperational effect by estimating some changes of root shape; secondly, stress distribution is also measured to analyze the result of preparation.Experiment 1: the purpose is to find the morphologic indexes to evaluate root preparation. Three simulated canals are prepared by three kinds of techniques respectively. Then they are scanned by micro-CT and analyzed by image processing software. Finally, we record the magnitude and position of root orifices, depict the outline of several transects respectively, calculate the segmental volume of root from root curve to orifice. The results indicate, step-back technique enlarges the root orifice. It removes more tissue on the bending side of root and orifice region. Reverse flaring technique has retained the shape of orifice, however, it still has the same cutting tendency with step-back technique on the upper part of root orifice. Crown-down technique (ProTaper) has better retention of orifice than step-back technique and it forms a regular root...