치아의 기하학적 특성을 이용한 3D 치과 임플란트 시술 계획 수립 방안 연구

Abstract

Recently, dental implants are becoming popular because of aesthetic and convenience in modern society. In order to increase the success rate for this, it is very important to establish an appropriate treatment plan before placement. Although recently a method of utilizing the 3D model based on dental medical image has been used widely, implant position and orientation are determined primarily by an operator's experience and subjective judgement. So this may lead to a deviation of the procedure. In this study, we propose a way to determine the position and direction of implant through the processing of the three-dimensional geometric model of the teeth and oral cavity. By using the method obtained above, we proposes a method for generating a surgical stents that can be used directly in the implant. 3D mesh model about teeth, jawbone, neural tube which were obtained through each patient medical image processing are used as an input data. A minimum enclosing cylinder is obtained by applying the Principal Component Analysis(PCA) algorithm to the teeth around treatment area. In the proposed method, the minimum enclosing cylinder is utilized importantly. A drilling position is placed on the interpolation curve line which is connecting the top center points of the minimum enclosing cylinders around operation area considering the radius of the surrounding teeth's cylinders. An implant's direction is determined through the average by considering the weight of the center axis of the surrounding cylinders. In addition, we estimates the maximum radius and length of a cylinder in an operation area by considering the interference between the surgery area and surrounding cylinders and neural model. This result is used when selecting size and type of an implant. Based on the direction and the position of implant, an 3D model of surgical stents are generated. And, we verified the validity of the method proposed by the finite element analysis. The proposed implant method can be useful as a dental implant education contents and it is also possible to provide useful information to establish an implant's plan.