天然型无机骨的制备及其成骨效应的实验研究

PROCESSING OF NATURAL NON ORGANIC BONE AND EXPERIMENTAL STUDY OF ITS EFFECT ON BONE FORMATION

已有多种材料修复骨缺损，但天然型无机骨（ｎａｔｕｒａｌｎｏｎ－ｏｒｇａｎｉｃｂｏｎｅ，ＮＮＢ）的骨作用研究较少。采用动物骨，经物理、化学及高温处理，除去其有机成分，保留其无机成分的三维结构外型。天然型无机骨既具有类似人骨的网状孔隙，又有利于传导成骨。植入家兔的肌肉、桡骨内和胫骨内，采用Ｘ线，组织学荧光标记等方法观察。证实，该材料组织相容性好，且具有新生骨出现早、生长快及成骨量多的特点。

Natural non organic bone(NNB) was obtained after the fresh bone of pig was heated to 100℃. The NNB was white and in a shape as its original bone.The tensile strength of the compact bone was 200kg/cm 3 and that of the cancellous bone was 25kg/cm 3. The ratio of calcium to phosphorus was 10∶6. The main component was hydroxyapatite. The material was composed of trabeculae and intertrabecular spaces. Three experiments were performed. Experiment 1: 18 pieces of NNB in a size of 0.5×0.5×0.5cm 3 were implanted into the back muscle of 18 rabbits. At 4, 8 and 12 weeks after the operation, 6 specimens were obtained seperately and were stained by HE, and then examined under microscope. The result showed that the mesenchymal cells had no regeneration and differentiation, and the NNB and the surrounding tissues had no evidence of formation of new bone or chondrosynthesis. This NNB did not produce rejection reaction between tissues but the new blood vessels could easily grow into the space of the NNB. The fibrils had intimate contact with NNB. Experiment 2: The NNB and hydroxyapatite(HA) were mixed to make a cylindroid body with 2mm in diameter and 4mm in length and was implanted in the bilateral tibias of 40 rabbits, respectively. The roentgenography, fluroscent microscopic examination and histological observation were carried out at 2, 3, 4 and 8 weeks after the implantation. Experiment 3: In 50 rabbits, a defect of 2.5cm was made on both radius, and in one side NNB was implanted and the other side was served as the control. Another 50 rabbits HA was implanted in the defect in one side and the other side was served as the control. The results showed that in the NNB group at the 16th week, the bone united in 16 of the 30 cases, while in the HA group, in the 30 cases, only 2 had the bone united, while those of the controls no union had occurred. It was suggested that NNB had more formation of new bone than HA did.