School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Taiwan.
Biomed Res Int. 2021 Mar 18;2021:5586498. doi: 10.1155/2021/5586498. eCollection 2021.
This study investigated the relationship between the shortest buccal bone marrow of the ramus and skeletal patterns.
Using cone-beam computed tomography data (specifically, the A point-nasion-B point (ANB) angle), we divided patients into three groups as follows: skeletal class I (0° < ANB < 4°), class II (ANB: ≥4°), and class III (ANB: ≤0°). Sixteen vertical sections in the coronal plane were taken starting from slice 0 (original intact mandibular canal) anteriorly at 2 mm intervals to slice 15 (30 mm). The thickness of the mandible (M) and shortest buccal bone marrow (SBM) were measured. The data of SBM were divided into two groups (SBM ≥ 1 mm and SBM < 1 mm). For each skeletal pattern, an SBM value < 1 mm was considered to indicate a high possibility of postoperative nerve paresthesia and bad split.
The three skeletal pattern groups also did not significantly differ in their M values for all sections. The mean SBM values of class III (0.91-2.11 mm) at 6-16 mm anterior to the mandibular foramen were significantly smaller than those of class II (1.53-3.17 mm). Comparing the occurrence ratio of SBM < 1 mm, the highest and lowest probabilities in class III (55% and 21.7%, respectively) were significantly larger at 6-20 mm anterior to the mandibular foramen than those in class II (28.3% and 5%, respectively).
Class III had a significantly shorter SBM distance and higher SBM occurrence probability than class II at the mandibular ramus region, implying that class III participants are more likely than class II participants to have nerve paresthesia and bad split after sagittal split ramus osteotomy.
本研究旨在探讨下颌升支颊侧骨板最窄处与骨骼形态之间的关系。
使用锥形束 CT 数据（具体为 A 点-鼻根点-B 点（ANB）角），我们将患者分为三组：骨骼 I 类（0°<ANB<4°）、II 类（ANB：≥4°）和 III 类（ANB：≤0°）。从前向后，在冠状面每隔 2mm 取 16 个垂直切片，从第 0 片（原始完整下颌管）开始，至第 15 片（30mm）。测量下颌骨（M）和颊侧骨板最窄处（SBM）的厚度。SBM 数据分为两组（SBM≥1mm 和 SBM<1mm）。对于每个骨骼形态，SBM<1mm 被认为是术后神经感觉异常和劈开不良的高可能性。
三组骨骼形态的 M 值在所有切片中也没有显著差异。III 类（6-16mm 前下颌孔）的 SBM 平均值（0.91-2.11mm）明显小于 II 类（1.53-3.17mm）。比较 SBM<1mm 的发生率，III 类（55%和 21.7%）在 6-20mm 前下颌孔的概率明显高于 II 类（28.3%和 5%）。
与 II 类相比，III 类在下颌升支区域的 SBM 距离明显更短，SBM 发生的概率更高，这表明 III 类患者在接受矢状劈开下颌支截骨术后发生神经感觉异常和劈开不良的可能性高于 II 类患者。
