Division of Head and Neck Surgery, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA.
Otolaryngol Head Neck Surg. 2011 Sep;145(3):404-10. doi: 10.1177/0194599811400576.
To develop a rat model of mandibular osteoradionecrosis(ORN) that uses novel micro-computed tomography bone volume analysis and detailed histology to provide a more effective, quantifiable, and standardized way to study ORN in vivo.
Animal model.
Academic medical center.
Modifications to our previously published rat model of mandibular ORN were done to develop an ideal protocol consisting of 10 rats (6 experimental and 4 controls) with their left middle mandibular molar removed 7 days after either 20 Gy high dose rate brachytherapy or sham irradiation. Rats were sacrificed 21 days after extraction for landmark defined bone volume and histologic analysis.
A standardized method of quantification was achieved in all samples. The radiated group (XRT) had a mean bone volume/total volume (BV/TV) of 13.8% compared to 65.9% for controls (P < .001). There were increases in osteoclasts and fibrosis, decreases in osteoblasts,and less bone in radiated samples with a mean (SD)of 5.91 (3.77) osteoclasts/high-powered field (HPF) and 4.00(1.83) osteoblasts/HPF in XRT samples compared to 1.08(1.08) osteoclasts/HPF and 22.49 (6.00) osteoblasts/HPF for controls (P <.001).
Our updated model continues to be clinically analogous to human mandibular ORN and improves the radiologic and histologic analysis of bony defects, providing a method for quantification of bone loss. Further cell-specific staining, including immunohistochemistry, can be used with this model to study potential cellular mechanisms of mandibular ORN and test any future therapeutic options.
开发一种使用新型微计算机断层扫描骨体积分析和详细组织学的大鼠下颌骨放射性骨坏死（ORN）模型，为体内 ORN 研究提供更有效、可量化和标准化的方法。
动物模型。
学术医疗中心。
对我们之前发表的大鼠下颌骨 ORN 模型进行了修改，以制定一个理想的方案，包括 10 只大鼠（6 只实验组和 4 只对照组），在接受 20 Gy 高剂量率近距离放射治疗或假照射后 7 天去除左中下颌磨牙。在提取后 21 天，对有标志定义的骨体积和组织学分析进行了处死。
在所有样本中都实现了标准化的定量方法。辐射组（XRT）的骨体积/总体积（BV/TV）平均值为 13.8%，而对照组为 65.9%（P <.001）。在辐射样本中，破骨细胞和纤维化增加，成骨细胞减少，骨量减少，平均（SD）有 5.91（3.77）个破骨细胞/高倍视野（HPF）和 4.00（1.83）个成骨细胞/HPF，而对照组分别为 1.08（1.08）个破骨细胞/HPF 和 22.49（6.00）个成骨细胞/HPF（P <.001）。
我们更新的模型继续在临床上类似于人类下颌骨 ORN，并改善了骨缺损的放射学和组织学分析，提供了一种量化骨丢失的方法。进一步的细胞特异性染色，包括免疫组织化学，可以与该模型一起使用，以研究下颌骨 ORN 的潜在细胞机制，并测试任何未来的治疗选择。
