锶磷灰石多孔陶瓷动物体内降解的实验研究

The biodegrades of porous ceramics of strontium substituted hydroxyapatite in vivo

采用溶液反应方法制备含5%(原子分数)锶的羟磷灰石(Sr-HA)原料,经干压成型、烧结后制得孔隙率约35%的圆片状多孔体,植入新西兰大白兔脊柱两侧背脊肌中,以纯羟磷灰石试样作为实验对照;通过扫描电镜、四环素荧光标记法观察种植体试样表面生物降解性和与周围软组织之间界面状况以及四环素荧光分布,评价锶磷灰石多孔陶瓷在动物软组织内的生物降解性、对组织生长的引导性等生物学行为。结果显示,锶磷灰石种植试样3个月时表面可见由于晶体降解而呈现出大量凹陷结构,凹陷结构的边缘较中心点的降解更为明显和快速;6个月时可观察到凹陷样结构处外围有明显的从外向内吸收特征,并且可观察到大量的强亮色条索状、团状荧光带,连成一片。而羟磷灰石对照组材料表面仅见少量的降解,四环素荧光呈点状弥散样,荧光强度较低。说明锶磷灰石具有良好的组织亲和性和组织引导性;与羟磷灰石相比,锶磷灰石的降解速度快,降解程度高。锶磷灰石可能具有诱导骨基质形成的作用。

The Sr-HA（hydroxyapatite containing 5at% Sr）porous ceramics and HA porous ceramics（as the positive contrast）with poriness of 31% were implanted into two side sacrospinal muscle of New Zealand rabbits.The interface between sample and muscle were observed with means of scanning electron microscopy and tetracycline fluorescent marker to evaluate the biodegradability and biologic capacity.The results indicated that the quantity of crystal body were observed to degrade into structure as bone lacunae on the surface of Sr-HA at three months,while control group hadn＇t much more appearance of degradation as time continued.Strong and bright fluorescent cingulum can be seen around Sr-HA at the six months.Sr-HA is a biomaterial with good biocompatibility and tissue conductivity.Sr-HA degrades faster and more completely than HA,and may induce bone matrix formation.