Bioceramics of calcium phosphate nano-structured micro-macro porous granules rapidly absorbed in filling critical radial defect in rabbits (Oryctolagus cuniculus)

ABSTRACT The objective of this study was to evaluate the effect of HA/ βTCP on rapid absorption granules in rabbit radiography, histology, and bone densitometry. Thirty - five male rabbits of the New Zealand breed were used and a critical defect was performed on the right and left radios. The animals were distributed in GI, autologous graft and GII HA / βTCP in rapidly absorbed granules. Radiographic, histological, and densitometry evaluations were performed before surgery, then after eight, 15, 30, 45 and 60 days. A significant difference was found when comparing the bone mineral density obtained over the study time. Formation of vascular network between the bioceramic pores was observed by the first evaluation time, (eight days). Primary bone tissue and trabeculae were observed from preexisting bone tissue after 30 days of implantation. At 60 days, the presence of bone matrix was observed from the preexisting bone segments, characterizing the centripetal bone formation. The micro-macroporous nanocomposite HA / βTCP of rapidly absorbing granules do not cause microscopic changes indicative of rejection, allows invasion, cell multiplication, and promotes bone regeneration, constituting an appropriate implant for filling of critical bone failures.

摘要
本研究旨在评估羟基磷灰石/β-磷酸三钙（HA/βTCP）快速吸收颗粒的骨修复效果，通过兔放射成像、组织学及骨密度测定开展相关评价。本研究选用35只新西兰品系雄性家兔，于双侧桡骨制备临界骨缺损模型。实验动物分为两组：GI组为自体移植组，GII组植入快速吸收型HA/βTCP颗粒。分别于术前及术后8、15、30、45、60天进行放射成像、组织学及骨密度检测。
本研究检测得到的骨矿密度在各研究时间点存在显著差异。术后8天首次评估时，即可观察到生物陶瓷孔隙内形成血管网络。植入30天后，可从原有骨组织中观察到原始骨组织及骨小梁形成。术后60天，可从原有骨段中观察到骨基质形成，呈现向心性骨生成特征。
本研究所用的微孔-大孔纳米结构快速吸收型HA/βTCP颗粒未引发可观测的排斥反应相关微观病理改变，可支持组织侵入、细胞增殖并促进骨再生，是一种适用于临界骨缺损填充的理想植入材料。