Department of Orthodontics, Institute of Stomatology, Riga Stradins University, Riga, Latvia.
Private practice, Baldone, Latvia.
Am J Orthod Dentofacial Orthop. 2023 Sep;164(3):340-350. doi: 10.1016/j.ajodo.2023.01.015. Epub 2023 Mar 31.
Facial aesthetics have become one of the most important objectives of orthodontic treatment. The correction of dental arches should be performed in accordance with the face. This study explored the association between occlusal and facial asymmetries in adolescents, particularly emphasizing a Class II subdivision.
Eighty-one adolescents (43 males, 38 females) with a median age of 15.9 (interquartile range, 15.17-16.33) years were enrolled. Of these patients, 30 had a Class II subdivision (right side, n = 12; left side, n = 18). Three-dimensional facial scans were analyzed using surface- and landmark-based methods. Chin asymmetry was determined using the chin volume asymmetry score. Three-dimensional intraoral scans were analyzed to assess occlusal asymmetry.
The surface matching scores were 59.0% ± 11.3% for the whole face and 39.0% ± 19.2% for the chin. Chin volume was larger on the right side than on the left side in most patients (n = 51, 63%), and it was associated with a dental midline shift to the corresponding subdivision side. A correlation between dental and facial asymmetries was noted. In addition, the dental midline shifted to the left in patients with a Class II subdivision, regardless of the side, and to the right in those with a symmetrical Class II subdivision. However, several patients did not possess asymmetrical occlusal traits sufficient for statistical analysis.
Dental asymmetry was weak but significantly correlated with facial asymmetry.
面部美学已成为正畸治疗的最重要目标之一。牙弓的矫正应符合面部。本研究探讨了青少年牙合与面不对称的关系,特别是强调了 II 类亚类。
共纳入 81 名青少年(男 33 例,女 48 例),中位年龄为 15.9 岁(四分位间距,15.17-16.33)。其中 30 例为 II 类亚类(右侧,n=12;左侧,n=18)。采用基于表面和标志点的方法分析三维面部扫描。使用颏部体积不对称评分来确定颏部不对称。分析三维口内扫描以评估牙合不对称。
全脸的表面匹配得分为 59.0%±11.3%,颏部为 39.0%±19.2%。大多数患者(n=51,63%)右侧颏部体积大于左侧,且与牙中线向相应亚类侧移位相关。牙合与面不对称之间存在相关性。此外,II 类亚类患者无论侧别,牙中线均向左移位,而 II 类对称亚类患者牙中线向右移位。然而,一些患者没有足够的统计分析所需的不对称牙合特征。
牙合不对称虽弱,但与面不对称显著相关。