纳米羟磷灰石/聚酰胺66盖髓的动物实验研究

目的研究新型纳米羟磷灰石／聚酰胺66复合生物材料(nHA—PA66)用作直接盖髓材料的组织学反应。方法采用犬作为动物实验模型，观察nHA—PA66直接盖髓7d、30d、60d后穿髓孔处牙髓创面修复性牙本质形成及炎症反应等组织病理学改变。氢氧化钙(Dycal)盖髓作为阳性对照。结果nHA—PA66盖髓后部分犬齿有修复性牙本质形成，其形成速度及形成样本数较氢氧化钙组少，但有修复性牙本质形成的样本其下方牙髓组织中的炎症反应较氢氧化钙组轻微，表明nHA—PA66对牙髓组织刺激性小，有较好的组织相容性和一定的促修复性牙本质形成能力。结论nHA—PA66用于犬齿盖髓具有较好的组织生物相容性，但促修复性牙本质形成能力较氢氧化钙差，是一种还有待改进和进一步深入研究的新型盖髓材料。

Experimental Study of the Pulpal Response of Dogs Capping with nHA-PA66

Objective To investigate the responses of dog pulp tissue to the new nano-hydroxyapatite/polyamide 66 biological composites (nHA-PA66) used as direct pulp capping agent. Methods Dogs were used in establishing the experimental model. The reparative dentin bridge formation and the histopathological changes at the pulp-exposed site were observed at 7, 30 and 60 days postoperatively. Calcium hydroxide (Dycal) was used as positive control. Results After capping with nHA-PA66, some dog teeth were found to have formation of reparative dentin bridge and slight inflammatory response during the pulp healing procedure when compared with the effect of using calcium hydroxide. Conclusion The results indicate that nHA-PA66 has good tissue biocompatibility, but its function of inducing reparative dentin bridge formation is not good enough as compared with that of calcium hydroxide. It has the potential to be used as a direct pulp capping agent, but further researches are needed.