激光扫描测量全口义齿钛基托适合性的可行性研究

The feasibility study of evaluating the quality of fit of Titanium complete denture base by laser scan technique.

目的:应用LSH600激光扫描设备,对全口义齿钛基托的适合性进行研究,探讨激光扫描法检测义齿基托适合性的可行性。方法:将制作好的上半口钛基托放置在无牙颌模型上,蜡封闭边缘后,装盒;待石膏凝固后,取出无牙颌模型,再次在型盒内灌制超硬石膏模型。待模型结固后,将两个模型分别置LSH600三维激光扫描仪工作台上的同一位置并固定,利用三维激光扫描模型组织面,获得三维点云数据。利用反求软件Surfacer10.0对获得的数据进行数据预处理,对两组数据间的差异进行自动分析。分析结果以颜色来显示两组数据重合情况。结果:通过激光三维扫描和数据三维拟合,钛基托适合性的最大误差0.352mm,平均误差0.135mm。结论:应用新型激光扫描法研究义齿基托适合性具有速度快、可靠性高的优点,可以较全面反映义齿基托的适合性。

Objective： To investigate the quality of fit of Titanium （Ti） of complete denture base by applying LSH600 laser scan technique, so as to provide experimental evidence to evaluate the feasibility of this new technique in studying the fitness of Ti complete denture base. Method： The fabricated Titanium base made by the traditional way was firstly fixed on the surface of its original maxillary edentulous plaster cast. The fringe around the Ti base and the plaster cast was sealed by wax. Then by dental flasking method and after the gypsum was solidified, the original maxillary edentulous plaster cast was removed through flask. Another plaster cast which duplicated the surface of the Ti base was then made on the same plane in the flask. Both of the plaster casts were slightly trimmed and were located in the same place of the LSH600 laser scan worktable and then the tissue surface of both casts was recorded as point clouds data by laser scan method. Both of the data was automatically compared to calculate the discrepancies between those of Ti base and plaster cast by applying reverse engineering software Surfacer10.0. The situation of coincidence between 2 groups of data was distinguished by different color which represented the distance between different regions. Result： By laser scan method and 3-D computing, the maximum error was 0.352 mm and the average error was 0.135 mm. Conclusion：This new method equipped with high reliability and fast speed can meet the need of the study of quality of fit. It is highlighted for its evaluation of the fitness of complete denture base all round.