数字化三维牙颌模型测量系统的可靠性对比研究

目的 检验由我院和清华大学共同研制开发的建立于层析扫描技术基础上的牙颌模型数字化三维重建系统之测量软件的可靠性。方法 选择不同牙列期的患者20例，常规取印模并灌制成两副牙颌模型，组成为两个配对的样本；其中样本1保留为石膏模型，样本2由三维模型重建系统生成数字化的模型影像；由同一操作者间隔3周分别对石膏模型和数字模型的牙齿宽度、牙弓宽度和牙弓长度等测量项目进行两次测量。结果 数字化模型两次测量结果的差值经秩和检验表明无统计学差异；经两组样本各测量项目两次测量结果之差数的￡检验表明，牙弓宽度两次测量结果的差异在石膏模型和数字模型间无显著性；而牙弓长度和牙齿宽度两次测量结果的差异具有显著性。结论 三维重建系统可生成真实的数字化牙颌模型影象，系统测量软件能提供可靠的测量数据且其精确性明显优于石膏模型。

A comparative study on the reliability of a digital 3D models measuring system

Objective To investigate the reliability of a newly developed sorftware of digital measuring 3D models reconstruction system.Methods Twenty patients with different dentitions were included in the study. Both stone and digital models of each patient were obtained. Tooth width?arch width and arch length were measured, respectively, on the stone and the digital models and remeasured by the same examiner 3 weeks after.Results No significant difference was observed between the means of the measurements performed at two different times on the digital models. A statistical significance was not found comparing the differences in the arch width measured at two different times. The differences of tooth width and arch length measured at two different times on digital models was significantly smaller compared to those of the stone counterparts.Conclusion Three-dimensional reconstruction system can offer virtual models and on-screen calipers which enables operator to review and analyze dental arch more freely and precisely in comparison with the stone models.