基于中空有机无机杂化纳米生物活性颗粒的新型牙体修复用复合树脂

Resin composites as the dental restoration materials have been widely used in clinical application, however, the marginal gap still be existed, which may lead to the secondary caries. Recently，bioactive particle have been added into the composites to promote tooth remineralization in oral environment and reduce the marginal gap, however, the mechanical property of the composites decreased, and they were not suitable for clinical use because of the worse compatibility between bioactive particles and resin matrix. In this project, we will prepare amphiphilic hollow organic/inorganic hybrid bioactive particles (nHBP), with different regions of microscale-compositions. The obtained nHBP were then blended with the resin matrix to prepare novel bioactive resin composites, with the filler well-distributed and an improvement of mechanical properties. Meanwhile, the bioactive materials can fully contact with saliva so that the hydroxyapatite(HA) layer formed rapidly on the surface of the material to bond with the surrounding tissues, which is expected to enhance the marginal integrity between the restoration materials and tooth, and then solve the problem of marginal gap. This project will mainly focus on the relationship between the structure of nHBP and the mechanical property of resin composites, the mineralization mechanism and degradation of the novel dental resin composite in artificial saliva, and the marginal integrity and bonding force between implants and tooth. The findings of this project will provide new ideas and materials for injured dental restoration, especially regarding the marginal gap issue.

复合树脂作为牙体修复材料已经广泛应用于临床，但其在应用过程中仍然存在边缘缝隙问题，从而导致继发龋的发生。近几年，研究者们尝试在复合树脂中引入生物活性颗粒，使其在口腔环境下形成矿化层，减小边缘缝隙，但由于现有生物活性颗粒与树脂基体的相容性问题，导致树脂力学性能显著下降，无法满足临床要求。本项目将制备表面具有微观组成分区的两亲性中空有机无机杂化纳米生物活性颗粒(nHBP)，与树脂基体复合得到生物活性复合树脂，使填料能够均匀分布在树脂基体中，改进材料力学性能，同时生物活性物质能充分与唾液接触而快速形成矿化层羟基磷灰石(HA)，与周边组织发生键合，从而提高修复体与牙体间的密合度，解决边缘缝隙问题。本项目将重点研究nHBP结构与复合树脂的性能的关系、复合树脂在模拟口腔环境下的矿化特性和降解行为以及植入体与牙体间的密合度和结合力，为受伤牙体修复提供新思路和新材料。

复合树脂作为牙体修复材料已经广泛应用于临床，但其在应用过程中由于聚合收缩会导致粘接失效，牙本质小管暴露，细菌侵入，从而导致继发龋的发生。近几年，研究者们尝试在复合树脂中引入生物活性玻璃，使其在口腔环境下形成矿化层，从而解决问题。但由于现有生物活性玻璃与树脂基体的相容性差，导致树脂力学性能显著下降，无法满足临床要求。本项目制备了表面具有微观组成分区的两亲性有机无机杂化复合纳米生物活性颗粒(BRP)，将其引入到复合树脂基体中，制备了新型复合树脂。研究发现：BRP与复合树脂具有良好的相容性，能够均匀分散于树脂基体中，显著的提高材料的力学性能，并改进了材料的吸水值和溶解值；BRP的引入使材料具有良好的生物活性，与口腔唾液接触7天后能够促使羟基磷灰石层的形成，能够促使牙本质表面形成致密的矿化层，并促使牙髓细胞的粘附和增殖。因此，BRP作为牙科复合树脂填料在临床研究方面将具有很大的潜力。