可塑形组织工程骨体内成骨的实验研究

Experimental study of bone regeneration of plastic-engineered bone in vivo

目的探讨用藻酸钙凝胶、成骨细胞、生物衍生颗粒骨复合构建可塑形组织工程骨及其修补兔颅骨缺损的体内成骨。方法24只日本大耳白兔,随机分为两组,用藻酸钙凝胶-成骨细胞-生物衍生颗粒骨和藻酸钙凝胶-生物衍生颗粒骨分别填补修复A组(16只)兔颅骨左右两侧直径1cm的圆形骨膜-全层颅骨缺损(左侧为A1组,右侧为A2组),B组(8只)为空白对照组。通过大体、组织学观察和图像分析、X线、钙磷含量测定评估其体内成骨状况。结果材料植入后,局部未见异常反应。(1)A1组手术后12周时颅骨缺损已基本被硬组织所修复,镜下见修复材料已大多被骨组织替代,颗粒骨被吸收,成骨面积百分比为(40.92±19.36)%,明显高于A2组(P<0.05)和B组(P<0.01)。X线片见兔颅骨缺损处有高密度骨痂影存在,布满整个缺损区。缺损修复组织的钙、磷含量分别为(7.30±0.93)mg、(3.11±0.42)mg,明显高于A2组和B组。(2)A2组手术后12周,颅骨缺损部分被硬性组织所修复,镜下见材料部分转变成骨组织和纤维组织,成骨面积百分比为(18.51±6.01)%,高于B组,但差异无统计学意义,X线片见兔颅骨缺损处高密度骨痂影主要分布在缺损区的边缘部位。缺损修复组织的钙、磷含量分别为(5.29±0.17)mg、(2.34±0.35)mg,明显高于B组。(3)B组骨缺损主要被膜样组织修复,在紧邻骨缺损处有硬组织形成,镜下见修复组织边缘有骨组织存在,中央大部为膜状致密纤维组织,成骨面积百分比为(12.72±9.46)%,X线片仅见靠近骨缺损边缘的部位存在致密骨痂影。缺损修复组织的钙、磷含量分别为(3.54±0.45)mg、(1.78±0.53)mg。结论藻酸钙凝胶-成骨细胞-生物衍生颗粒骨构建的可塑形组织工程骨可根据颅骨缺损的形态进行塑形填补,在体内有良好的成骨能力,可基本达到对兔颅骨缺损的骨性修复。

Objective To construct the plastic-engineered bone prefabricated with alginate gel, osteoblast and bone granules or alginate and bone granules and investigate its effect in repairing the rabbit cranial defects. Methods A total of 24 Japanese white rabbits were randomly divided into Group A and Group B. Bilateral cranial defects for 1 cm in diameter were created and the left defects considered as Group AI （n = 16） and the right defects as Group A2 （n =8）. Group AI were filled with alginate gel-osteoblast-bone granules and Group A2 with alginate gel-bone granules. Group B was used as blank control. Bone regeneration in vivo was observed by means of gross analysis, morphology, image analysis, X ray and measurement of content of calcium and phosphate. Results No abnormal reactions such as red swelling or effusion were seen after implantation of the materials. Twelve weeks after operation in Group A1, many bone-like masses appeared in the newly formed tissues and the tissues surrounding the bone granules partially changed into bone-like tissues, with bone regeneration percentage for （40. 92 ± 19.36） %, which was significantly higher than that in Group A2 （ P 〈 0. 05 ） and Group B （ P 〈 0.01 ）. X-ray showed that the skull defects were almost entirely repaired by hard tissues. The amount of Calcium and Phosphorus of tissues repairing the defects was （ 7.30 ± 0. 93 ） mg and （ 3.11 ± 0. 42 ） mg respectively in Group AI, which were significantly higher compared with both Group A2, in which the amount of Calcium and Phosphorus was （ 5.29 ± 0. 17 ） mg and （ 2.34 ± 0. 35 ） mg and Group B that has the amount of Calcium and Phosphorus for （ 3.5 4 ± 0. 4 5 ） mg and （ 1 . 7 8 ± 0. 5 3 ）mg respectively. In Group B ,the skull defects were mainly repaired by membrane-like soft tissues with only few bone in marginal area. Radiogram showed that the area of skull defects of Group A1 were full of high-density shade with obvious contrast that high dense shade only occurred in the marginal area of skull defects of group B. Conclu- sion Engineered bone constructed with alginate gel-osteoblast-bone granule may shape according to the bone defects and can basically repair cranial defects of the rabbits for it has the nice ability to in vivo form bone tissue.