两种取模方法对全冠适合性影响的比较研究

Comparative study of two impression methods in full crown adaption

目的评价光学扫描和硅橡胶取模后模型扫描制作的计算机辅助设计和制作(CAD-CAM)全冠的适合性。方法分别使用光学扫描(A组)和硅橡胶印模后模型扫描(B组)切削制作左下颌第一磨牙的CAD-CAM树脂全冠(n=10)。采用硅橡胶复制法在显微镜下测量全冠的粘接剂空间。结果两组全冠的边缘适合性分别为(44.38±9.64)和(42.39±13.02)μm(P=0.817)、内部适合性分别为(80.26±31.71)和(75.25±6.07)μm(P=0.729),两组在各测量位点上所得的粘接剂厚度的差异无统计学意义(P>0.05)。A组不同测量位点间粘接剂空间的值差异较小,B组同一测量位点粘接剂空间的值较为集中。结论两种取模方法所得的全冠的边缘和内部适合性无差异,均在临床可接受范围之内。

Objective To investigate the application of optical impression and model scanning after silicone rubber impression in full crowns adaption by Computer Aided Design and Computer Aided Manufacturing （CADCAM）. Methods Ceramic full crown was prepared for Mandibular left first molar （Nissin Dental Products, Japan）. Impressions were made by optical scanning （group A） or silicone rubber （group B） （n = 10）. The adaption of crowns was measured by silicone replica technique and inverted phase contrast microscope （Olympus BX43）. All data was processed using SPSS 20.0 for statistical analysis. Results Marginal adaptation （μm） in group A and group B was （44.38 ± 9.64） and （42.39 ± 13.02） （P = 0.817）, respectively. Occlusal adaptation （μm） was （80.26 ± 31.71） and （75.25 ± 6.07） （P = 0.729）, respectively. No significant difference was founded between two groups in terms of cement thickness （P 〉 0.05）. Cement space among different measurement sites in group A was similar, while cement space at the same measurement site in group B was more centralized. Conclusion Two methods are comparable in marginal adaptation and internal adaptation, both of which are clinically acceptable.