重组人骨形成蛋白-2复合胶原I盖髓的实验研究

目的:观察重组人骨形成蛋白-2复合胶原I的盖髓效果和对牙髓组织骨钙素含量的影响，探讨牙髓细胞分化和修复性牙本质形成的机制，为临床筛选理想的盖髓材料提供实验依据。方法:以30只猫为实验对象，机械暴露牙髓后，分别用重组人骨形成蛋白-2复合胶原I、氢氧化钙、胶原及对照的牛血清白蛋白盖髓，运用组织学方法观察牙髓修复性牙本质的形成及牙髓组织学改变，采用放射免疫分析技术检测盖髓后1周、2周、4周时牙髓组织骨钙素的含量。结果:与氢氧化钙、胶原和牛血清白蛋白盖髓比较，用重组人骨形成蛋白-2复合胶原I盖髓，能形成完整的管样牙本质桥，牙髓组织骨钙素的含量显著多于正常牙髓。结论:重组人骨形成蛋白-2复合胶原I盖髓可诱导形成完整的牙本质桥，显著增加牙髓组织骨钙素的含量。重组人骨形成蛋白-2复合胶原I作为生物活性盖髓剂，起到良好的活髓保存效果，值得临床推广应用。

The experimental study on rhBMP-2 combined with type I collagen as pulp capping agent in cats

AIM: To assess the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) combined with type I collagen on pulp capping in cats. METHODS： Freshly exposed pulps of thirty cats were capped with four different pulp capping agents: rhBMP-2/collagen I, calcium hydroxide, type I collagen and bovine serum albumin as control. The reparative dentinogenesis and osteocalcin content were assessed after 1 week, 2 weeks and 4 weeks by means of histology and radioimmunoassay. RESULTS: the pulpal tissues of the teeth capped with rhBMP-2/collagen showed mild inflammation and odontoblast differentiation with tublar dentin bridge on the exposed site. The level of bone γ-carboxyglutamic containing protein(BGP) in the group of rhBMP-2 with collagen I was significantly higher than that of the other three groups (P＜0.01). CONCLUSTION: rhBMP-2 combined with type I collagen is a bioactive pulp-capping agent and has a great worth in vital pulp therapy.