锥束CT数字化模型与石膏模型在牙颌测量中的对比研究

摘要

Objective:To determine if the measurements obtained from digital model of cone beam computedtomography (CBCT) images are comparable to those from traditional plaster model. Methods: Digital and plaster jaw models of 23 subjects were prepared respectively. NNTViewer software was used to analyze CBCT scans taken by a NewTom Vgi cone beam scanner. Digital vernier caliper was used to analyze the plaster study models. The linear parameters of Littles Index, overjet, overbite, Bolton ratio and the Howes Index were measured on the paired models respectively. Results: All of the parameters were found to be normally distributed. The paired t-test showed no statistical difference between the data from digital and plaster models(P >0. 05) in linear dental measurements, but there was statistical difference in linear bone measurements( P <0. 01 ). Conclusion: CBCT digital models are as accurate as plaster models in linear dental measurements and may be more accurate than plaster model in linear bone measurements.%目的:确定利用锥束CT(CBCT)数字化牙颌模型测量得到的数据与石膏模型测量数据是否具有一致性.方法:对23例患者的锥束CT数字化模型和石膏模型进行配对研究.使用NNTViewer软件分析由NewTom VGi锥束CT扫描仪所形成的三维牙颌模型,同时制取超硬石膏模型.由测量人员分别对2种模型进行Little指数、前牙覆(牙合)覆盖、Bolton指数、HOWES指数等线性数据重复测量,对比分析测量结果.结果:所有的测量数据呈正态分布.配对t检验表明用于测量上颌骨和下颌骨的牙性指标差异均无显著性.在上下颌骨骨性结构的测量中2种模型之间的差异具有统计学意义.结论:CBCT的数字模型和石膏模型在牙性线性测量具有一致性,在骨性结构测量数据相对石膏模型具有更好的可重复性与精确性.