Nahidh Mohammed
Department of Orthodontics, University of Baghdad School of Dentistry, Iraq.
Turk J Orthod. 2018 Dec;31(4):117-121. doi: 10.5152/TurkJOrthod.2018.18006. Epub 2018 Dec 1.
This study aimed to develop regression equations to predict the combined mesiodistal widths of maxillary and mandibular incisors from each other and compare them with other methods.
One hundred pairs of study models from 100 Iraqi subjects with normal occlusion were used in this study. The individualized mesiodistal widths of maxillary and mandibular incisors were measured using electronic digital calipers. The combined mesiodistal widths of maxillary and mandibular incisors were calculated according to Tonn's and Abhi's formulas and from regression equations to be compared with the actual one.
Both sums of the maxillary and mandibular incisors were significantly correlated. There were significantly high differences between the actual and calculated sum widths, and also between the calculated and predicted ones. On the other hand, a non-significant difference was obtained between the actual and predicted sum widths of maxillary and mandibular incisors.
Tonn's and Abhi's methods are not reliable methods to calculate the sum widths of maxillary and mandibular incisors. New regression equations are developed to predict the sum widths of maxillary and mandibular incisors from each other.
本研究旨在建立回归方程，以相互预测上颌和下颌切牙的近远中宽度总和，并将其与其他方法进行比较。
本研究使用了100名伊拉克正常咬合受试者的100对研究模型。使用电子数字卡尺测量上颌和下颌切牙的个体化近远中宽度。根据托恩（Tonn）和阿比（Abhi）的公式以及回归方程计算上颌和下颌切牙的近远中宽度总和，并与实际宽度进行比较。
上颌和下颌切牙的宽度总和均具有显著相关性。实际宽度总和与计算宽度总和之间以及计算宽度总和与预测宽度总和之间存在显著差异。另一方面，上颌和下颌切牙的实际宽度总和与预测宽度总和之间无显著差异。
托恩和阿比的方法不是计算上颌和下颌切牙宽度总和的可靠方法。建立了新的回归方程以相互预测上颌和下颌切牙的宽度总和。
