Faculty of Dentistry, The University of Hong Kong, SAR, China.
Eur J Orthod. 2010 Oct;32(5):589-95. doi: 10.1093/ejo/cjp159. Epub 2010 Feb 17.
The objective of this study was to assess the feasibility of virtual models as an alternative to orthodontic plaster models. Virtual dental models (obtained from OrthoCAD) and corresponding plaster models of 80 patients in the permanent dentition were randomly selected from patients seeking orthodontic care. Inter-examiner error was assessed by measuring tooth width, overjet, overbite, intermolar width, intercanine width, and midline discrepancy. Criterion validity of virtual model analysis was determined by the agreement between the measurements from virtual and plaster models. Test-retest reliability was determined by remeasuring 10 virtual models 1 week later. Comparison analysis was assessed by calculating the mean directional differences and standardized directional differences. Correlation analysis was determined by calculating the intraclass correlation coefficients (ICCs). Both intra- and inter-examiner reliability and test-retest reliability of virtual model analysis were acceptable in measuring intercanine, intermolar, overjet, overbite, midline discrepancy, space analysis, and tooth width (ICC > 0.7). Good criterion validity was indicated by agreement between the results from the plaster and virtual models (ICC > 0.8). There were substantial agreements for canine and molar relationship classifications (κ > 0.70). The results suggest that analysis performed on virtual models is as valid as traditional plaster models for intra- and inter-arch relationship.
本研究旨在评估虚拟模型作为替代传统正畸石膏模型的可行性。从寻求正畸治疗的患者中，随机选择 80 名恒牙患者的虚拟牙模（通过 OrthoCAD 获得）和相应的石膏模型。通过测量牙宽度、覆𬌗、覆盖、磨牙间宽度、尖牙间宽度和中线差异，评估了检查者间的误差。通过比较虚拟模型和石膏模型的测量值，确定了虚拟模型分析的准则效度。通过重新测量 10 个虚拟模型 1 周后的测量值，确定了测试-重测可靠性。通过计算平均方向差异和标准化方向差异，评估了比较分析。通过计算组内相关系数（ICC），确定了相关性分析。在测量尖牙间、磨牙间、覆𬌗、覆盖、中线差异、间隙分析和牙宽度时，虚拟模型分析的内-检查者和外-检查者可靠性和测试-重测可靠性均具有可接受性（ICC > 0.7）。石膏模型和虚拟模型结果之间的一致性表明具有良好的准则效度（ICC > 0.8）。在尖牙和磨牙关系分类方面具有实质性的一致性（κ > 0.70）。结果表明，虚拟模型分析与传统的石膏模型相比，在牙弓内和牙弓间的关系分析上具有同等的有效性。
