Mutinelli Sabrina, Cozzani Mauro, Manfredi Mario, Siciliani Giuseppe
Department of Orthodontic, University of Ferrara, Ferrara, Italy.
Prog Orthod. 2004;5(2):200-11.
The purpose of our research is to describe a computerized method, which enables orthodontists and researchers to analyze variation of dental arch form and dimension. The analysis system is composed of two independent parts: the database, where the images of scanned dental casts are stored, and the software. The operator uses the software to identify some landmarks on dental cast images. Corresponding distances are calculated (interincisive, intercanine and intermolar widths and the curve axis). Then the software algorithms calculate and draw the curves passing trough the selected landmarks (conics, catenary, cubic spline and polynomial curves). In the chosen curves the arch length is measured. The dental cast data, recorded at different times of the subject's life or in different steps of orthodontic treatment, are compared in order to evaluate the change in dimension (arch length and width) and form (shape). The statistical analysis of the data evaluates the variation in form and in dimension separately. The shape change is defined by Euclidean Distance Matrix Analysis (EDMA) and Bootstrap analysis. The computerized method allows orthodontists and researches to evaluate the variation in dimension and form of the dental arch in un-treated subjects and-or orthodontic patients over time. After the analysis of a large sample of patients or subjects, information concerning changes in dental arch dimension and form can be added to previous studies of other authors, distinguishing variation during and after orthodontic treatment, during growth or aging.
我们研究的目的是描述一种计算机化方法，该方法能使正畸医生和研究人员分析牙弓形态和尺寸的变化。该分析系统由两个独立部分组成：数据库，用于存储扫描牙模的图像；以及软件。操作人员使用该软件在牙模图像上识别一些标志点。计算相应的距离（切牙间、尖牙间和磨牙间宽度以及曲线轴）。然后软件算法计算并绘制通过所选标志点的曲线（圆锥曲线、悬链线、三次样条曲线和多项式曲线）。在所选曲线中测量牙弓长度。比较在受试者生命不同时期或正畸治疗不同阶段记录的牙模数据，以评估尺寸（牙弓长度和宽度）和形态（形状）的变化。对数据的统计分析分别评估形态和尺寸的变化。形状变化通过欧几里得距离矩阵分析（EDMA）和自举分析来定义。这种计算机化方法使正畸医生和研究人员能够评估未经治疗的受试者和/或正畸患者随时间推移牙弓尺寸和形态的变化。在对大量患者或受试者进行分析后，有关牙弓尺寸和形态变化的信息可以添加到其他作者先前的研究中，区分正畸治疗期间和之后、生长或衰老过程中的变化。
