Stevens Daron R, Flores-Mir Carlos, Nebbe Brian, Raboud Donald W, Heo Giseon, Major Paul W
Orthodontic Graduate Program, Department of Dentistry, University of Alberta, Edmonton, Alberta, Canada.
Am J Orthod Dentofacial Orthop. 2006 Jun;129(6):794-803. doi: 10.1016/j.ajodo.2004.08.023.
The objective of this validation study was to compare standard plaster models (the current gold standard for cast measurements) with their digital counterparts made with emodel software (version 6.0, GeoDigm, Chanhassen, Minn) for the analysis of tooth sizes and occlusal relationships--specifically the Bolton analysis and the peer assessment rating (PAR) index and their components.
Dental casts were poured from 24 subjects with 8 malocclusion types grouped according to American Board of Orthodontics categories. Measurements were made with a digital caliper to the nearest 0.01 mm from plaster models and with the software from the digital models. A paired samples t test was used to compare reliability and validity of measurements between plaster and digital methods.
Reproducibility of digital models via the concordance correlation coefficient was excellent in most cases and good in some. Although statistically significant differences in some measurements were found for the reliability and validity of the digital models via the average mean of the absolute differences of repeated measurements, none was clinically significant. Grouping of the measurements according to the 8 American Board of Orthodontics categories produced no significant difference (Kruskal-Wallis test). No measurement associated with Bolton analysis or PAR index made on plaster vs digital models showed a clinically significant difference. The PAR analysis and its constituent measurements were not significantly different clinically between plaster and emodel media.
Preliminary results did not indicate that digital models would cause an orthodontist to make a different diagnosis of malocclusion compared with plaster models; digital models are not a compromised choice for treatment planning or diagnosis.
本验证研究的目的是将标准石膏模型（目前用于模型测量的金标准）与其使用eModel软件（版本6.0，GeoDigm，明尼苏达州查哈森）制作的数字对应模型进行比较，以分析牙齿大小和咬合关系，特别是Bolton分析、同行评估评级（PAR）指数及其组成部分。
从24名受试者的牙模中灌注模型，这些受试者根据美国正畸委员会的分类分为8种错牙合类型。使用数字卡尺对石膏模型进行测量，精确到最接近的0.01毫米，并使用软件对数字模型进行测量。采用配对样本t检验来比较石膏模型和数字模型测量的可靠性和有效性。
在大多数情况下，通过一致性相关系数评估，数字模型的可重复性极佳，在某些情况下良好。尽管通过重复测量的绝对差值的平均值发现数字模型在某些测量的可靠性和有效性方面存在统计学上的显著差异，但均无临床意义。根据美国正畸委员会的8种分类对测量结果进行分组，未产生显著差异（Kruskal-Wallis检验）。在石膏模型和数字模型上进行的与Bolton分析或PAR指数相关的测量均未显示出临床显著差异。在临床方面，石膏模型和eModel介质之间的PAR分析及其组成测量无显著差异。
初步结果表明，与石膏模型相比，数字模型不会导致正畸医生对错牙合做出不同的诊断；数字模型在治疗计划或诊断方面并非折中的选择。
