Comparative evaluation of a biomimic collagen/ hydroxyapatite/β-tricaleium phosphate scaffold in alveolar ridge preservation with Bio-Oss Collagen

Bone scaffolds are critical in current implant and periodontal regeneration approaches. In this study, we prepared a novel composite type-I collagen and hydroxyapatite （HA）/β-tricaleium phosphate （TCP） scaffold （CHTS） by incorporating type-I collagen and bovine calcined bone granules, prepared as a mixture of 50% HA and 50% TCP, by freeze drying. We then characterized the CHTS and determined its cytotoxic effects. Additionally, ridge preservation experiments were carried out to evaluate the clinical effects of the CHTS. The results demonstrated that the composite scaffolds had good surface morphology and no cytotoxicity. Additionally, an in vivo experiment in an animal model showed that the CHTS performed equally as well as Bio-Oss Collagen, a widely used bone graft in ridge preservation. These findings revealed that the CHTS, which contained natural constituents of bone, could be used as a scaffold for bone regeneration and clinical use.

骨髓基质细胞复合三维支架修复犬下颌骨节段性缺损

目的:探讨犬骨髓基质细胞(bone marrow stromal cells,BMSCs)体外复合预制三维下颌骨缺损仿真β-磷酸三钙(β-TCP)支架对犬下颌骨节段性缺损进行修复的可行性。方法:通过计算机辅助设计/制作和快速原型技术,制作3cm长犬下颌骨节段性缺损β-磷酸三钙支架,体外接种第3代骨髓基质细胞,培养5d天后回植,对犬一侧下颌骨节段性缺损进行修复,并设单纯材料作为对照组。术后1周、1个月、3个月观察局部伤口情况,术后1、3个月行X线片和三维CT成像,术后3个月将标本进行生物力学检测和组织学观察。结果:X线片观察显示,术后3个月,对照组缺损区低密度影,BMSCs+β-TCP组缺损区见高密度组织;三维CT成像显示术后3个月,对照组修复区吸收明显,达1/2以上;BMSCs+β-TCP组修复区未见明显吸收;生物力学检测显示,对照组和BMSCs+β-TCP组的牙槽嵴高度分别为9.16mm和18.54mm,最大弯曲载荷分别为42.90N和102.77N,应力分别为1.930N/mm2和3.504N/mm2,应变分别为54.50%和16.98%。经统计学处理,均有显著性差异;组织学观察显示术后3个月,BMSCs+β-TCP组成骨良好,支架周围可见多核巨细胞吞噬材料,并可见软骨形成区。结论:应用β-TCP三维支架复合犬BMSCs进行犬下颌骨节段性缺损修复存在一定的可行性。

新型磷酸钙人工骨的代谢及骨转化现象

目的 研究β-磷酸三钙(β-TCP)多孔支架材料在生物体内的骨转化现象。方法 采用^(45)Ca同位素标记β-TCP多孔陶瓷材料,研究材料植入后的降解产物Ca^(2+)在体内的分布情况。结果 材料降解产生的Ca^(2+)随血循环到达软组织后不发生积累;而在股骨近端、尺骨干、颅骨中可被机体重新利用。结论 材料参与了全身骨组织的钙化并被储存于钙库中。