Khouri Christian, Aoun Georges, Khouri Carlos, Saade Maria, Salameh Ziad, Berberi Antoine
Department of Oral and Maxillofacial Surgery, Faculty of Dental Medicine, Lebanese University, P.O. Box 5208-116, Beirut, Lebanon.
Department of Oral Medicine and Maxillofacial Radiology, Faculty of Dental Medicine, Lebanese University, Beirut, Lebanon.
J Maxillofac Oral Surg. 2022 Jun;21(2):599-607. doi: 10.1007/s12663-020-01415-x. Epub 2020 Jul 16.
Classifications of impaction based on panoramic radiographs such as the ones of Pell and Gregory and Winter are essential to allow a better understanding of third molar position regarding depth and bone coverage of the impacted tooth and to evaluate the difficulties of the surgical procedures. The aim of the study was to classify upper and lower third molars teeth in a sample of a Lebanese population and compare the data to results from other studies.
Digital panoramic radiographs of 71 patients with a total of 181 wisdom teeth from patients that had been subjected for third molars extraction, from November 2016 to November 2018, were collected and analyzed. The mean age was 26.25 years. All third molars were categorized according to Pell and Gregory by using A, B, C scores for depth in upper and lower third molars, and angulations were classified according to Winter's classification. Nonparametric normality tests evaluating age group and gender distribution were conducted by utilizing the Chi-square test for age distribution and the binomial and Kruskal-Wallis tests for gender.
In the Pell and Gregory classification, the lower third molars showed type B impaction as the most frequent with 66.1% for the right side and 60.3% for the left side; the maxillary third molars both showed the type C impaction as the most frequent with 63.3% for the right side and 59.2% for the left side. According to the Winter classification, lower third molars showed mesio-angulation as the most frequent angle of impaction with 41.1% for right mandibular side and 46.5% for mandibular left side; As for the maxillary third molars, the disto-angulation was the most frequent angulation seen in both maxillary right and left side teeth 53.3% and 43.2%.
Comparison of our results with other populations has shown similarities in certain criteria like angulation and relation to ramus, but most results varied. Thus, the current study can be taken as a baseline for further studies.
基于全景X线片的阻生分类，如佩尔和格雷戈里以及温特的分类，对于更好地了解第三磨牙在深度和阻生牙骨覆盖方面的位置以及评估手术操作的难度至关重要。本研究的目的是对黎巴嫩人群样本中的上下颌第三磨牙进行分类，并将数据与其他研究结果进行比较。
收集并分析了2016年11月至2018年11月期间71例接受第三磨牙拔除患者的数字全景X线片，共181颗智齿。平均年龄为26.25岁。所有第三磨牙根据佩尔和格雷戈里分类法，用上颌和下颌第三磨牙的深度A、B、C评分进行分类，角度根据温特分类法进行分类。采用卡方检验评估年龄分布，采用二项式检验和克鲁斯卡尔 - 沃利斯检验评估性别分布，进行非参数正态性检验。
在佩尔和格雷戈里分类中，下颌第三磨牙B型阻生最为常见，右侧为66.1%，左侧为60.3%；上颌第三磨牙均以C型阻生最为常见，右侧为63.3%，左侧为59.2%。根据温特分类法，下颌第三磨牙近中倾斜阻生最为常见，右侧下颌为41.1%，左侧下颌为46.5%；而上颌第三磨牙，远中倾斜阻生在上颌右侧和左侧牙齿中最为常见，分别为53.3%和43.2%。
将我们的结果与其他人群进行比较，发现在某些标准上存在相似之处，如角度和与下颌支的关系，但大多数结果有所不同。因此，本研究可作为进一步研究的基线。
