Colak H, Ozcan E, Hamidi M M
Department of Restorative Dentistry, Kirikkale University School of Dentistry, Kirikkale, Turkey.
Niger J Clin Pract. 2012 Jul-Sep;15(3):306-10. doi: 10.4103/1119-3077.100627.
This retrospective study was undertaken to determine the prevalence of three-rooted permanent mandibular first molars in digital periapical radiographic images obtained from a Turkish patient.
Periapical radiographs of 640 subjects, which had been obtained in the Department of Oral Diagnosis Radiology, Kirikkale University Dental Faculty, Kirikkale, Turkey from June 2010 to March 2011, were screened and examined retrospectively. All radiographs were evaluated under optimal conditions using double magnifying glasses. Each radiograph was separately evaluated by two authors (H.Ç. and M.M.H.). Comparison of the incidence and the correlations between males and females and left- and right-side occurrences were analyzed by using the Pearson chi-square test with SPSS (15.0; SPSS Inc., Chicago, IL, USA).
The periapical radiographs of 9 patients, 4 females and 5 males, had three-rooted mandibular first molars. Of these three-rooted mandibular first molars, 7 were found on the right side and 5 on the left side. The overall incidence of patients with three-rooted mandibular first molars was 1.41%. The incidence was 1.63% for men and 1.2% for women.
The prevalence of three-rooted mandibular first molars from all teeth examined was 1% (12 of 1205), 1.17% (7 of 596) for the right side, and 0.82% (5 of 528) for the left side occurrences.
本回顾性研究旨在确定从一名土耳其患者获得的数字化根尖片影像中三根下颌第一恒磨牙的患病率。
回顾性筛查并检查了2010年6月至2011年3月在土耳其基尔卡莱大学牙科学院口腔诊断放射科获得的640名受试者的根尖片。所有根尖片均在最佳条件下使用双放大镜进行评估。每张根尖片由两位作者（H.Ç.和M.M.H.）分别评估。使用SPSS（15.0；SPSS公司，美国伊利诺伊州芝加哥）的Pearson卡方检验分析男性与女性以及左侧与右侧出现情况之间的发生率及相关性。
9名患者（4名女性和5名男性）的根尖片中出现了三根下颌第一磨牙。在这些三根下颌第一磨牙中，右侧发现7颗，左侧发现5颗。三根下颌第一磨牙患者的总体发生率为1.41%。男性发生率为1.63%，女性为1.2%。
在所检查的所有牙齿中，三根下颌第一磨牙的患病率为1%（1205颗牙齿中有12颗），右侧为1.17%（596颗牙齿中有7颗），左侧为0.82%（528颗牙齿中有5颗）。
