Smith B R, Rajchel J L, Waite D E, Read L
Department of Oral and Maxillofacial Surgery, University of Texas Dental Branch, Houston.
J Oral Maxillofac Surg. 1991 Mar;49(3):222-6; discussion 227. doi: 10.1016/0278-2391(91)90209-5.
Rigid fixation of osteotomy segments is frequently used to reduce relapse and allow for early mobilization of the mandible following the sagittal ramus split osteotomy. This study evaluated cortical bone thickness in the retromolar area of 49 human mandibles to determine if there is an advantage (in terms of cortical thickness) to placement of screws for rigid fixation at the external oblique ridge versus placement at the inferior border. The mandibles were sectioned vertically at three sites in the retromolar area, corresponding to the bone available for rigid fixation of the sagittal osteotomy. Cortical bone thickness was measured at the external oblique ridge and 5 mm above the inferior border. The buccal and lingual cortices were found to be significantly (P less than .001) thicker at the external oblique ridge than at the inferior border. This suggests that there may be an advantage in terms of stability to placement of internal fixation screws at the superior border.
截骨段的坚固固定常用于减少复发，并允许在矢状升支劈开截骨术后早期活动下颌骨。本研究评估了49例人类下颌骨磨牙后区的皮质骨厚度，以确定在皮质厚度方面，将用于坚固固定的螺钉置于外斜线处与置于下颌下缘处相比是否具有优势。在下颌骨磨牙后区的三个部位垂直切片，对应于可用于矢状截骨坚固固定的骨。测量外斜线处和下颌下缘上方5毫米处的皮质骨厚度。发现外斜线处的颊侧和舌侧皮质比下颌下缘处明显更厚（P小于0.001）。这表明在上缘处放置内固定螺钉在稳定性方面可能具有优势。
