Scomparin L, Soares M-Q-S, Rubira C-M-F, Yaedú R-Y-F, Imada T-S-N, Centurion B-S, Tolentino E-S, Lauris J-R-P, Rubira-Bullen I-R-F
Faculdade de Odontologia de Bauru, Alameda Otavio Pinheiro Brisolla 9-75, Bauru- SP, CEP 17012-901, Brazil,
Med Oral Patol Oral Cir Bucal. 2017 Jul 1;22(4):e500-e505. doi: 10.4317/medoral.21632.
Mandibular Sagittal Split Osteotomy (MSSO) is a popular technique in orthognathic surgery used both to advance and to retreat the mandible. However, MSSO may incur in important complications, such as bad splits and sensorineural injuries. Knowing the location of the fusion between the buccal and lingual cortical (FBLC) in the mandibular ramus and the bone thickness in the region where osteotomies will be performed is determinant in MSSO planning to avoid complications. The aim of this study was to document and evaluate possible differences between sexes regarding the location of the FBLC in relation to the superior cortical of mandibular foramen (MF) and bone thickness in the region of interest for MSSO in a Brazilian population.
Eighty five cone-beam Computed Tomography (CBCT) scans were used to perform linear measurements to determine the location of the FBLC. Bone thickness from the mandibular canal (MC) to the cortical external surfaces and the diameter of the MC were measured at three different points: mandibular ramus (A), mandibular angle (B) and mesial of the second molar (C).
The FBLC was located at a mean distance of 8.3 mm from the superior cortical of the MF in males and 8.1 mm in females. There was no difference between males and females regarding the mean bone thickness from the MC to the buccal external surface at all the points investigated (p>0.05). Bone thickness from the lingual external surface to the MC was bigger among females than males in regions B and C (p < 0.05). The diameter of the MC was bigger among males in regions B and C.
Sexual dimorphism regarding mandibular bone thickness but not regarding the location of FBLC was present. This fundamental knowledge may assist to the panning of MSSO.
下颌矢状劈开截骨术（MSSO）是正颌外科中一种常用的技术，用于下颌骨的前徙和后退。然而，MSSO可能会引发一些重要并发症，如劈裂不良和感觉神经损伤。了解下颌升支颊侧和舌侧皮质融合处（FBLC）的位置以及截骨部位的骨厚度，对于MSSO手术规划以避免并发症至关重要。本研究的目的是记录和评估巴西人群中，男女在FBLC相对于下颌孔（MF）上皮质的位置以及MSSO感兴趣区域的骨厚度方面可能存在的差异。
使用85例锥形束计算机断层扫描（CBCT）进行线性测量，以确定FBLC的位置。在下颌升支（A）、下颌角（B）和第二磨牙近中（C）三个不同点测量从下颌管（MC）到皮质外表面的骨厚度以及MC的直径。
男性FBLC距MF上皮质的平均距离为8.3mm，女性为8.1mm。在所有研究点，男性和女性从MC到颊侧外表面的平均骨厚度没有差异（p>0.05）。在区域B和C，女性从舌侧外表面到MC的骨厚度大于男性（p<0.05）。在区域B和C，男性的MC直径更大。
在下颌骨厚度方面存在性别差异，但在FBLC位置方面不存在性别差异。这一基础知识可能有助于MSSO手术的规划。
