基于逆向工程研究不同牙体预备形态对全冠三维适合性的影响  

Effects of different tooth preparations on three-dimensional adaption of crowns based on the reverse engineering

作　　者：夏媛[1,2] 谭发兵[2,3] 王璐[1,2] 吴树洪[2,3] 

机构地区：[1]重庆医科大学附属口腔医院修复科,重庆401147 [2]重庆医科大学口腔疾病与生物医学重庆市重点实验室,重庆401147 [3]重庆医科大学附属口腔医院修复工艺科,重庆400015

出　　处：《华西口腔医学杂志》2015年第5期470-473,共4页West China Journal of Stomatology

摘　　要：目的基于逆向工程研究不同牙体预备形态对计算机辅助设计与制作(CAD/CAM)全冠三维适合性的影响。方法扫描左上颌第一磨牙牙预备体并在NX Imageware 13.2软件中构建5种不同形态的牙预备体,将每种牙预备体导入exocad软件中分别制作8个树脂内冠。最后扫描树脂内冠粘接面,在Geomagic Qualify 12软件中进行适合性的三维分析。结果 3D偏差色谱图显示,深凹面形肩台组各区域偏移较小且大小均一;其余组各区域偏移相差较大,尤其是线角尖锐区域。深凹面形肩台、135°肩台、羽状肩台、直角翘边肩台、尖锐牙尖形态组的三维偏移值分别为(16.88±2.83)、(26.88±3.61)、(53.56±4.30)、(51.38±4.46)、(47.19±4.62)μm。深凹面形肩台组的适合性优于135°肩台组,差异有统计学意义(P<0.05);而直角翘边肩台组、尖锐牙尖形态组、羽状边缘组的整体适合性最差,三者比较差异无统计学意义(P>0.05)。结论计算机三维分析法是一种研究冠适合性的较好方法;推荐临床制备线角圆钝、深凹面形肩台的牙预备体;避免制备羽状、直角翘边边缘以及线角尖锐形态的牙预备体。Objective To investigate the effects of different tooth preparations on three-dimensional adaption of computer aided design and computer aided manufacturing （CAD/CAM） crowns based on the reverse engineering. Methods The tooth preparation model of the left maxillary first molar was scanned to build five different tooth preparations using the NX Imageware 13.2 software. The resin cores （n=8） were designed with the exocad software. The scanning data of the inner surface of each resin core were used to analyze the three-dimensional adaption with the Geomagic Qualify 12 software. Results According to the color-coded deviation images, the deviation of the heavy chamfer shoulder was the smallest and the most uniform, whereas the other groups with sharp lines showed large deviation. After statistical analysis, the total deviation of the heavy chamfer shoulder, 135° shoulder, feather shoulder, 90° shoulder with lipped margins, and sharp marginal ridges preparation were （16.88±2.83）, （26.88±3.61）, （53.56±4.30）, （51.38±4.46）, and （47.19±4.62） μm. A statistical significance was observed between the heavy chamfer and 135~ shoulders （P〈0.05）. The other groups fitted poorly, without statistical significance between each group （P〉0.05）. Conclusion Three-dimensional analysis using a computer is a preferable method to study the threedimensional adaption of crowns. The heavy chamfer shoulder and round line preparation are clinically recommended. However, feather shoulder, 90° shoulder with lipped margins, and sharp marginal ridge preparation should be avoided.

关 键 词：全冠 计算机辅助设计与制作 三维适合性 逆向工程 三维分析 

分 类 号：R783.3[医药卫生—口腔医学]