Raw data from mandibular measurements and fracture pattern classification

Considering the possible influence of the bone thickness on the fracture pattern after bilateral sagittal split osteotomy (BSSO). Pre and immediate postoperative tomographies in DICOM format of 62 surgical sites submitted to BSSO were analyzed by Dolphin 3D software. Preoperative analyses: 4 thickness measurements: A - 1.5 milimeter (mm) above the lingula. B - 1mm from the anterior border of the ramus. C - 5mm distally to the second molar and 5mm from the upper border of the mandible (retromolar region) D - Region between the first and second molars. Postoperative CT scans: Used to classify the split pattern in I, II, III or IV. The data were analyzed by Kruskal-Wallis test followed by the Dunn post-test. Results showed 35 type I, 01 type II, 19 type III and 07 type IV. Type I presented the highest thickness average values for the four measurements, whereas type IV presented the lowest values. The variable bone thickness was statistically significant only for point A, when the types I and IV were compared. Results allowed to conclude that thinner mandibles at ramus are more prone to bad splits and thickness at points B, C and D did not influence the fracture patterns.本研究旨在探讨骨厚度对双侧矢状劈开截骨术（Bilateral Sagittal Split Osteotomy, BSSO）后骨折类型的潜在影响。本数据集纳入62例接受该手术的手术部位的术前及术后即刻DICOM格式断层影像，采用Dolphin 3D软件进行分析。术前分析包含4项骨厚度测量指标：A点：舌侧隆突上方1.5mm处；B点：下颌支前缘1mm处；C点：第二磨牙远中5mm且距下颌骨上缘5mm处（磨牙后区）；D点：第一与第二磨牙之间的区域。术后CT扫描用于将劈开类型分为I、II、III、IV四型。采用Kruskal-Wallis检验结合Dunn事后检验对数据进行分析。结果显示，I型35例、II型1例、III型19例、IV型7例。I型的四项测量指标的骨厚度平均值均为最高，而IV型则为最低。仅在比较I型与IV型时，A点的骨厚度变量具有统计学显著性。研究结果表明，下颌支较薄的病例更易出现不良劈开，而B、C、D点的骨厚度对骨折类型无显著影响。