Benemérita Universidad Autónoma de Puebla, Facultad de Estomatología, Academia de Pediatría, Puebla, México.
Benemérita Universidad Autónoma de Puebla, Facultad de Estomatología, Academia de Ciencias Básicas, Puebla, México.
Acta Odontol Latinoam. 2021 Aug 1;34(2):149-155. doi: 10.54589/aol.34/2/149.
The aim of this study was to determine prevalence and describe the clinical and radiographic findings of three-rooted primary mandibular first and second molars in a Mexican population. Intraoral periapical radiograph, orthopantomogram or cone beam computed tomography (CBCT) were obtained. A total 2284 children from the state of Puebla, Mexico were examined, of whom 20 presented an anatomic variant in tooth crown shape. Of the total teeth with crown alterations, 10 first and 5 second primary mandibular molars were found to have supernumerary roots. In one case, it was possible to obtain micro-CT images. The study recorded prevalence, unilateral or bilateral occurrence, and ratio between sexes. Data were analyzed using descriptive statistics. Clinical findings were presence of an anatomical variation (tuberculum paramolare / right and/or left cervical convexity) in primary mandibular first molars. Second molars presented conventional crown morphology. Prevalence of three-rooted primary mandibular first and second molars was 0.44% and 0.22%, respectively. Male: female ratio for presence of threerooted primary mandibular first molars was 4:1, showing genetic predisposition in males, and for second molars it was 1.5:1, with no predisposition according to sex. The clinical and radiographic anatomical variants in primary molars should be considered by pediatric dentists during routine care because they may cause difficulties in restorations.
本研究旨在确定在墨西哥人群中，下颌第一和第二乳磨牙存在三根牙的流行率，并描述其临床和影像学表现。获取口腔根尖片、全景片或锥形束 CT（CBCT）。对来自墨西哥普埃布拉州的 2284 名儿童进行了检查，其中 20 名儿童的牙冠形态存在解剖变异。在总共有牙冠改变的牙齿中，发现 10 颗下颌第一乳磨牙和 5 颗下颌第二乳磨牙存在额外根。在其中一个病例中，能够获得微 CT 图像。该研究记录了患病率、单侧或双侧发生以及性别比例。使用描述性统计进行数据分析。临床发现为下颌第一乳磨牙存在解剖变异（副磨牙结节/右侧和/或左侧颈嵴凸起）。第二乳磨牙呈现常规牙冠形态。下颌第一和第二乳磨牙存在三根牙的患病率分别为 0.44%和 0.22%。存在下颌第一乳磨牙三根牙的男性：女性比例为 4:1，表明男性存在遗传易感性，而第二磨牙的比例为 1.5:1，性别无倾向性。在常规治疗中，儿科牙医应考虑到乳磨牙的临床和影像学解剖变异，因为它们可能导致修复困难。
