【作者】 曹山松； 宋秀环； 张旭； 陈阵；

【Author】 Cao Shansong;Song Xiuhuan;Zhang Xu;Chen Zhen;Stomatology School of Tianjin Medical University;

【机构】 天津医科大学口腔医学院；

【摘要】 目的:利用牙本质龋模型验证新型羧甲基壳聚糖/无定形磷酸钙(CMC/ACP)支架在脱矿牙本质再矿化中的作用。方法:通过在离体牙(牙合)制备近髓洞型并使洞底牙本质适当脱矿来建立人工龋模型,利用髓腔内循环模拟体液来模拟洞底牙本质小管内的液体交换,应用冷冻干燥工艺制备CMC/ACP支架,并于洞底水环境中缓慢释放钙磷,诱导脱矿洞底再矿化。采用micro-CT定性定量评估再矿化效果,通过电子显微镜检测支架内的钙磷形态并验证纤维内外矿化的发生。结果:支架电镜检测表明支架内大部分的钙磷处于小直径无定形状态。再矿化处理两周后,micro-CT检测显示再矿化区牙本质密度明显增高,再矿化深度为334.47±12.15μm,再矿化率为64.63±7.21%,再矿化牙本质透射电镜可见Ⅰ型胶原纤维内矿化典型的横纹征及D-band,选区电子衍射可见典型的晶体衍射环,扫描电镜显示牙本质内脱矿后塌陷的胶原和牙本质小管重新膨胀饱满。结论:CMC结合冷冻干燥工艺能够长时间的将钙磷稳定在无定形状态,且CMC/ACP在水环境下能够高效的促进脱矿牙本质再矿化。更多还原

【Abstract】 Objective:The aim of this study was to remineralize completely demineralized dentine in a tooth model of deep caries using nanocomplexes of carboxymethyl chitosan/amorphous calcium phosphate(CMC/ACP) based on mimicking the stabilizing effect of dentine matrix protein 1(DMP1) on ACP in the biomineralization of dentine.Method:CMC/ACP scaffolds were first prepared and then were put in a tooth model of deep caries to test its remineralization ability.Results:The experimental results indicate that CMC can stabilize ACP to form nanocomplexes of CMC/ACP,which is able to be processed into scaffolds by lyophilization.In the tooth model,nanocomplexes of CMC/ACP are released from CMC/ACP scaffolds to accomplish intrafibrillar remineralization of completely demineralized collagen using bottom-up strategy based on non-classical crystallization theory,thus facilitating remineralization of dentine.Conclusion:Since nanocomplexes of CMC/ACP show a promising effect of remineralization on demineralized dentine via biomimetic strategy,thereby preserving dentinal tissue to the maximum extent possible,it would be a potential IPC material for the management of deep caries based on the concept of minimally invasive dentistry(MID).更多还原