São Leopoldo Mandic College, Department of Orthodontics, Brasília, Federal District, Brazil.
Department of Orthodontics, University of Brasília, Brasília, Federal District, Brazil.
Am J Orthod Dentofacial Orthop. 2022 Jun;161(6):e580-e587. doi: 10.1016/j.ajodo.2022.03.007. Epub 2022 Apr 13.
This retrospective study evaluated the buccal bone thickness in mandibular canine, premolar, and molar areas, using as a reference the WALA ridge in patients with various facial patterns.
The sample comprised 51 cone-beam computerized tomography scans of subjects divided into 3 groups according to the facial pattern, determined by the Ricketts' VERT index, brachyfacial (group 1), mesofacial (group 2), and dolichofacial (group 3). A quantitative analysis of the buccal bone thickness was made in cone-beam computerized tomography scans in the region of the mandibular dental arch corresponding to the WALA ridge. The intergroup comparison of buccal bone thickness was performed with a 1-way analysis of variance and Tukey tests.
Buccal bone thickness was similar among the groups, and it increased progressively from the mandibular first to the second molars. In the canine and premolar regions, the thickness was less and often not visible on tomography. There was no difference in the buccal bone thickness in the mandibular dental arch region corresponding to the WALA ridge reference among facial patterns, except for the mesial roots of the second molars, which were thicker in brachyfacial subjects than in dolichofacial subjects.
The use of the WALA ridge as a clinical reference for individualized orthodontic arch diagramming should be made with caution and independent of the facial pattern.
本回顾性研究通过 WALA 嵴评估了不同面型患者下颌尖牙、前磨牙和磨牙区颊侧骨皮质厚度。
该样本包括 51 例锥形束计算机断层扫描(CBCT),根据 Ricketts' VERT 指数将受试者分为 3 组,短面型(组 1)、中面型(组 2)和长面型(组 3)。在 CBCT 扫描中,对下颌牙弓对应 WALA 嵴的区域进行颊侧骨皮质厚度的定量分析。采用单因素方差分析和 Tukey 检验进行组间比较。
各组间颊侧骨皮质厚度相似,且从下颌第一磨牙到第二磨牙逐渐增加。在尖牙和前磨牙区,颊侧骨皮质厚度较薄,且在 CT 上通常不可见。除第二磨牙近中根外,WALA 嵴参考区域的下颌牙弓颊侧骨皮质厚度在不同面型之间无差异,而第二磨牙近中根在短面型受试者中比在长面型受试者中更厚。
在进行个体化正畸牙弓图设计时,使用 WALA 嵴作为临床参考应谨慎,并独立于面型。