纳米磷酸钙联合季铵盐改性正畸粘接系统的机制研究

Enamel demineralization around the brackets has been proved as the most common side effect that is of major clinical relevance in orthodontic treatment. The use of a fixed orthodontic appliance based on brackets and archwires generally tends to accumulate more dental plaque biofilm, and leads to an increased risk of demineralization and caries. Dental plaque biofilm is on the one hand, a direct result of certain oral infectious diseases, for instance caries, on the other hand can produce acid and demineralization, thus more likely to cause bacterial accumulation. .Application of nanotechnology and contact antimicrobial quaternary ammonium monomer to combat enamel demineralization and prevent caries becomes a new research hot spot. Extensive studies have been performed to demonstrate that calcium phosphate nanoparticles are promising to prevent dentin demineralization and promote dentin remineralization. Quaternary ammonium monomer has also been proved to possess a long-lasting antibacterial effect. It has been confirmed that even when taking preventive efforts into account, there is a continued risk of initiating or even increasing enamel demineralization during treatment with fixed orthodontic appliances. Current researches mostly focus on the dentin bonding system. Therefore, it is important to develop novel antibacterial and remineralizing orthodontic bonding system because brackets are bonded to enamel via bonding agents. Orthodontic bonding system with antibacterial properties can stabilize oral micro-ecological environment, arrest or remineralize early lesions and maintain the health of the oral microbial environment. .Therefore, the objectives of this study were to incorporate both calcium phosphate nanoparticles and antimicrobial quaternary ammonium monomer into orthodontic bonding agents, and to investigate their combined effects on bond strengh, dental plaque microcosm biofilm viability, and remineralization-promoting properties for the first time.

牙釉质的脱矿及龋坏一直是正畸治疗中最常见也是最难控制的治疗风险之一，而纳米技术的应用和接触性抗菌剂季铵盐是防治该问题的一个新的研究方向。前期研究认为，纳米磷酸钙是一种具有潜力的预防牙体硬组织脱矿和促进再矿化的物质，季铵盐能够发挥持久的接触抑制性抗菌作用，但是目前的研究主要集中在牙本质粘接系统中的使用，缺少对牙釉质粘接系统-正畸粘接剂中防龋和促进牙釉质再矿化方面的研究。本课题针对正畸粘接剂缺乏抗菌性和促进牙釉质再矿化能力的问题，构建体外牙菌斑微生态系模型，从降低牙菌斑致龋性和调节牙釉质矿化平衡两个方面进行研究，通过联合使用纳米磷酸钙和季铵盐，在赋予正畸粘接系统防龋性能的同时不影响其粘接性能，并合成新型纳米复合物，探讨其发挥抗菌、防脱矿和促进再矿化的作用的机制。探索新型纳米材料在正畸治疗中防止牙釉质脱矿和龋坏的应用，并为口腔抗菌材料的基础研究及临床应用提供有价值的参考和新的思路。

牙釉质的脱矿及龋坏一直是正畸治疗中最常见也是最难控制的治疗风险之一，而纳米技术的应用和接触性抗菌剂季铵盐是防治该问题的一个新的研究方向。前期研究认为，纳米磷酸钙是一种具有潜力的预防牙体硬组织脱矿和促进再矿化的物质，季铵盐能够发挥持久的接触抑制性抗菌作用，但是目前的研究主要集中在牙本质粘接系统中的使用，缺少对牙釉质粘接系统-正畸粘接剂中防龋和促进牙釉质再矿化方面的研究。本课题针对正畸粘接剂缺乏抗菌性和促进牙釉质再矿化能力的问题，构建体外牙菌斑微生态系模型，从降低牙菌斑致龋性和调节牙釉质矿化平衡两个方面进行研究，通过联合使用纳米磷酸钙和季铵盐，在赋予正畸粘接系统防龋性能的同时不影响其粘接性能，并合成新型纳米复合物，探讨其发挥抗菌、防脱矿和促进再矿化的作用的机制。将该纳米合成物添加到正畸粘结剂中，开发出新型纳米正畸粘结剂，在正畸治疗中能够防止牙釉质脱矿和龋坏，并为口腔抗菌材料的基础研究及临床应用提供有价值的参考和新的思路。