无牙颌口内数字化印模技术可行性的初步探究

Preliminary study on the feasibility of digital impression technology in edentulous complete denture

目的:通过对上颌无牙颌口内数字化印模与间接数字化印模精度进行对比,探讨采用数字化印模技术进行无牙颌印模的可行性。方法:随机选取10例上颌牙列缺失的患者,使用TRIOS口内扫描仪直接获取患者上颌解剖式印模,标记为直接印模组(DP);同时使用传统方法制作有孔的个别托盘,使用轻压力来获取同一患者的上颌无牙颌解剖式印模,灌注模型后使用TRIOS口内扫描仪和3shape810模型扫描仪分别扫描其石膏模型,标记为口外印模组(OP)和间接印模组(IP)。将三组数字化印模两两导入GeomagicWrap2015软件中,进行模型配准和3D拟合分析。以IP组作为参照,采用单因素方差分析和配对t检验分别进行组内和组间数据分析,比较TRIOS三代扫描仪扫描口内及模型的黏膜变形量大小。结果:TRIOS三代口内扫描仪在临床上可以有效快速的扫描上颌无牙颌,其扫描口内及模型相对于模型扫描仪扫描模型的精度均具有统计学差异(P<0.05),口内直接扫描的误差为0.312±0.085 mm,口外间接扫描模型的误差为0.125±0.056 mm。误差主要集中于无牙颌边缘、腭中缝和后堤区等区域,牙槽嵴及上颌硬区处偏差较小。结论:目前口内扫描仪在操作上可以实现快速获取上颌无牙颌光学印模,但仍需解决其精度不足的问题,间接扫描模型的精度高于直接扫描口内。

Objective:By comparing the accuracy of direct digital impression and indirect digital impression of the edentulous,the feasibility of using digital impression technology for complete denture was discussed.Methods:Ten patients with maxillary edentulous jaws were selected,and anatomical maxillary impressions were taken directly using the TRIOS intraoral scanner and labeled as direct impressions(DP);at the same time,individual trays with holes were made using the traditional method,and anatomical maxillary edentulous impressions of the same patients were taken using light pressure.The plaster models were scanned using the TRIOS intraoral scanner and the 3shape810 model scanner,respectively,and labeled as extraoral impression group(OP)and indirect impression group(IP).The three groups of digital impressions were imported into GeomagicWrap2015 software for model alignment and 3D fitting analysis.Using the IP group as a reference,one-way ANOVA and paired t-test were used to analyze the data within and between groups,respectively,to compare the magnitude of mucosal deformation in the intraoral and model scanned by the TRIOS 3 scanner.Results:The TRIOS 3 intraoral scanner was clinically effective and rapid in scanning the maxillary edentulous jaws,and the accuracy of its scanning intraoral and model relative to the model scanner was statistically different(P<0.05),with an error of 0.312±0.085 mm for direct intraoral scanning and 0.125±0.056 mm for indirect extraoral scanning of the model.The errors were mainly concentrated in the edentulous margin,palatal suture and posterior dike area,and the deviations were smaller in the alveolar ridge and maxillary hard area.Conclusion:The current intraoral scanner can be operated to achieve rapid acquisition of optical models of maxillary edentulous jaw impressions,but it is still necessary to solve the problem of its lack of accuracy,and the accuracy of indirectly scanned models is higher than that of directly scanned intraoral.