Boston, Mass. From the Department of Plastic and Oral Surgery, Children's Hospital Boston, Harvard Medical School; the Program in Oral and Maxillofacial Pathology, Harvard School of Dental Medicine; and the Department of Orthopedic Surgery, Brigham and Women's Hospital, Harvard Medical School.
Plast Reconstr Surg. 2012 May;129(5):796e-802e. doi: 10.1097/PRS.0b013e31824a2bdd.
Cranial particulate bone graft heals inlay calvarial defects and can be harvested as early as infancy. The purpose of this study was to test the hypothesis that particulate bone promotes ossification primarily by osteogenesis.
Freshly harvested particulate bone, devitalized particulate bone, and high-speed drilled bone dust from rabbit calvaria were assayed for metabolic activity (resazurin) and viable osteoblasts (alkaline phosphatase). A rabbit cranial defect model was used to test the effect of devitalizing particulate bone on in vivo ossification. A parietal critical-size defect was created and managed in three ways: (1) no implant (n = 6); (2) particulate bone implant (n = 6); and (3) devitalized particulate bone implant (n = 6). Micro-computed tomographic scanning was used to measure ossification 16 weeks later; histology also was studied.
Particulate bone contained more viable cells (0.94 percent transmittance per milligram) compared with devitalized particulate bone (0.007 percent) or bone dust (0.21 percent) (p = 0.01). Particulate bone had greater alkaline phosphatase activity (0.13 μU/μg) than devitalized particulate bone (0.000) or bone dust (0.06) (p = 0.01). Critical-size defects treated with particulate bone had more ossification (99.7 percent) compared with devitalized particulate bone implants (42.2 percent) (p = 0.01); no difference was found between devitalized particulate bone and the control (40.8 percent) (p = 0.9).
Particulate bone graft contains living cells, including osteoblasts, that are required to heal critical-size cranial defects. These data support the hypothesis that particulate bone promotes ossification primarily by osteogenesis.
颅粒子骨移植物可修复嵌入式颅骨缺损，并可早在婴儿期即可采集。本研究的目的是验证这样一个假设，即颗粒状骨主要通过成骨作用促进骨化。
对取自兔颅骨的新鲜颗粒骨、失活颗粒骨和高速钻骨粉进行代谢活性（resazurin）和活成骨细胞（碱性磷酸酶）检测。采用兔颅缺损模型检测失活颗粒骨对体内成骨的影响。创建一个顶骨临界尺寸缺陷，并以三种方式进行管理：（1）无植入物（n=6）；（2）颗粒骨植入物（n=6）；（3）失活颗粒骨植入物（n=6）。16 周后，采用微计算机断层扫描测量骨化情况；还进行了组织学研究。
颗粒骨比失活颗粒骨（0.007%）或骨粉（0.21%）（p=0.01）含有更多的活细胞（每毫克 0.94%透光率）。颗粒骨的碱性磷酸酶活性（0.13μU/μg）高于失活颗粒骨（0.000）或骨粉（0.06）（p=0.01）。用颗粒骨治疗的临界尺寸缺陷的骨化程度（99.7%）高于失活颗粒骨植入物（42.2%）（p=0.01）；失活颗粒骨与对照组（40.8%）之间无差异（p=0.9）。
颗粒状骨移植物含有活细胞，包括成骨细胞，这些细胞是修复临界尺寸颅骨缺损所必需的。这些数据支持这样一个假设，即颗粒状骨主要通过成骨作用促进骨化。
