Toodehzaeim Mohammad Hossein, Haerian Alireza, Alesaeidi Ali
Associate Professor, Department of Orthodontics, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Assistant Professor, Department of Orthodontics, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
J Dent (Tehran). 2016 Nov;13(6):383-387.
Proper diagnosis and prevention of malocclusion are superior to treatment. Discrepancy between arch length and tooth size in mixed dentition period is a condition requiring timely diagnosis. Estimating the mesiodistal width of unerupted teeth according to the size of erupted ones can lead to earlier diagnosis of malocclusion. On the other hand, the best timing for serial extractions is before the eruption of lateral incisors. The aim of this study was to present prediction formulas for mesiodistal width of unerupted lateral incisors, canines and premolars in an Iranian population based on the width of erupted permanent mandibular central incisors and maxillary first molars.
A total of 120 dental models (60 males, 60 females) of orthodontic patients between 11-25 years were evaluated in Yazd city. The measurements were made by a digital caliper on the widest mesiodistal width of teeth at the interproximal contacts. Data were analyzed to calculate the prediction equation.
The prediction equation in the upper jaw was y=0.57x+10.82 for males, y=0.7x+6.37 for females and y=0.64x+8.46 for both sexes. The equation for the lower jaw was y=0.76x+2.86 for males, y=0.74x+3.53 for females and y=0.77x+2.7 for both sexes.
The prediction equations suggested in this study can predict the mesiodistal width of unerupted lateral incisors, canines and premolars in an Iranian population in early mixed dentition period without taking radiographs.
错牙合畸形的正确诊断和预防优于治疗。混合牙列期牙弓长度与牙体大小的差异是需要及时诊断的情况。根据已萌出牙齿的大小估计未萌出牙齿的近远中宽度可导致错牙合畸形的早期诊断。另一方面,序列拔牙的最佳时机是在侧切牙萌出之前。本研究的目的是基于已萌出的下颌恒中切牙和上颌第一磨牙的宽度,提出伊朗人群中未萌出的侧切牙、尖牙和前磨牙近远中宽度的预测公式。
对亚兹德市11至25岁正畸患者的120个牙模(60名男性,60名女性)进行评估。使用数字卡尺在牙邻面接触处测量牙齿最宽的近远中宽度。分析数据以计算预测方程。
上颌的预测方程男性为y = 0.57x + 10.82,女性为y = 0.7x + 6.37,男女合并为y = 0.64x + 8.46。下颌的方程男性为y = 0.76x + 2.86,女性为y = 0.74x + 3.53,男女合并为y = 0.77x + 2.7。
本研究提出的预测方程可在不进行影像学检查的情况下,预测伊朗人群在混合牙列早期未萌出的侧切牙、尖牙和前磨牙的近远中宽度。