Rachmiel A, Laufer D, Jackson I T, Lewinson D
Department of Oral and Maxillofacial Surgery, Rambam Medical Center, Haifa 31096, Israel.
Calcif Tissue Int. 1998 Apr;62(4):370-6. doi: 10.1007/s002239900447.
Midface bone lengthening was performed on three young, adult sheep using distraction osteogenesis following osteotomy of the maxilla and mounting of an extraoral fixation device. The midface was gradually distracted, 2 mm/day, for 21 days, up to approximately 40 mm. A marked midface advancement was noted. Following a further 6 weeks of retention, the device was removed and the animals were followed for 1 year. Biopsies specimens were taken from the distracted area at the end of the distraction period, after the additional 6 weeks of retention, and finally 1 year later. A nondistracted area of the maxillary bone served as control. The specimens were analyzed histologically, histochemically, and by scanning electron microscopy for the ultrastructural pattern, mineralization, mineral content, and approximate Ca2+ concentration. Clinically and radiographically, all sheep fully bridged the experimental gap. Histologically, at the completion of distraction, collagen bundles and slender bone trabeculae oriented in the direction of the distraction could be seen. At the end of the retention period, the trabeculae thickened noticeably and were partially replaced by mature lamellar bone. At the end of 1 year and after completion of the process of remodeling, the pattern of the distracted area resembled the control area. The mineralization, as reflected by quantitative calcium analysis, compared with the nondistracted area, demonstrated a low rate of mineralization after 3 weeks of lengthening, increased 6 weeks later, and after 1 year became nearly the same as in the nondistracted area. In conclusion, distraction osteogenesis provides satisfactory quantitative and structural new bone.
对三只成年幼羊进行面中部骨延长术，采用上颌骨截骨术后外置固定装置并通过牵张成骨技术进行。面中部以每天2毫米的速度逐渐牵张，持续21天，直至约40毫米。可见明显的面中部前移。在再固定6周后，拆除装置并对动物随访1年。在牵张期结束时、额外再固定6周后以及最后1年后，从牵张区域获取活检标本。上颌骨未牵张区域作为对照。对标本进行组织学、组织化学分析，并通过扫描电子显微镜观察超微结构模式、矿化、矿物质含量及近似钙离子浓度。临床和影像学检查显示，所有绵羊均完全弥合了实验间隙。组织学检查发现，牵张结束时，可见胶原束和沿牵张方向排列的细长骨小梁。再固定期结束时，骨小梁明显增粗，并部分被成熟板层骨替代。1年后重塑过程完成时，牵张区域的形态与对照区域相似。通过定量钙分析反映的矿化情况，与未牵张区域相比，牵张3周后矿化率较低，6周后升高，1年后几乎与未牵张区域相同。总之，牵张成骨可提供令人满意的定量和结构性新骨。
