净尺寸仿生釉质结构牙科陶瓷的快速成型及其性能研究

Ceramic materials are widely used in dental restorations because of its unique characteristics. However, comparing with the natural tooth tissue, there still exists a large gap for ceramics to be improved on the structural and mechanical properties, which indicating the forming process of the ceramics is in need of further development. Therefore, it is of great theoretical and practical significance to optimize the design and fabrication of new dental ceramics based on the concept of biomimetic. By referring to the concept of interpenetrating polymer networks in industry, three-dimensional scaffold of biomimetic ceramics will be designed according to sophisticated structure of enamel. Afterwards, water-based photosensitive zirconia toughened alumina ceramics slurries will be used as raw material, while Stereo Lithography Apparatus combining with thermal polymerization technique will be applied to obtain the enamel-structure-liked architecture of the ceramic preforms. And then, the mechanical properties and microstructure of this novel ceramic will also be performed. Finally, the relationship between microstructure and mechanical properties would be systematically analyzed by using Finite Element Analysis, while the performance matching between new ceramic materials and natural tooth enamel will also be explored. The results of this comprehensive study will clearly interpret the core process of new technology on the preparation of biomimetic net-shaped ceramics. Through this study, it will not only offer a viable route for the fabrication of biomimetic dental ceramics, but also provide the theoretical basis in the improvement of Stereo Lithography Apparatus, and ultimately make a solid foundation for the clinical application of this novel ceramic.

陶瓷材料因其独特的优越性能被广泛应用于牙体缺损及缺失修复；然而，与天然牙体组织相比，其在结构及力学性能匹配上仍有较大差距；这提示现有牙科陶瓷材料的成型工艺仍需进一步改善提高。因此，基于仿生理念优化设计并制备新型牙科陶瓷材料具有重要的理论及现实意义。本项目模拟天然牙釉质微观结构，借鉴工业网络互穿复相聚合物概念，设计仿生陶瓷三维支架结构；利用课题组研发的水基光敏氧化锆增韧氧化铝陶瓷浆料，结合光固化成型技术，并联合热聚合渗透树脂工艺，制备净尺寸仿生釉质结构新型牙科陶瓷材料；探究该新型陶瓷材料与天然牙釉质性能匹配差异，进一步阐明陶瓷显微结构仿生优化与力学性能相关关系，从而诠释牙科陶瓷仿生净尺寸成型新技术的核心工艺及其对陶瓷性能影响规律。本研究不仅为结构及性能仿生牙科陶瓷新材料的设计与制备奠定理论基础，也为光固化快速成型牙科陶瓷制作增加技术支持，并最终为该新型陶瓷的牙科临床应用提供实验依据。

牙科陶瓷是牙齿缺损缺失修复的首选材料，但与天然牙体组织相比，其在结构及力学性能匹配上仍有较大差距；因此寻求一种与天然牙体组织各方面性能相匹配的新型陶瓷材料具有重要的临床意义。本项目基于天然牙釉质的独特结构及其优越性能，设计仿釉质结构模型；选用课题组前期研发的氧化锆增韧氧化铝 (Zirconia-Toughened Alumina, ZTA) 陶瓷粉体作为原料，优化光敏ZTA陶瓷浆料配方，调整ZTA 陶瓷浆料的各材料组分，制备出符合光固化成型设备技术要求的兼具高固相含量及良好流动性的陶瓷浆料配方，并筛选适宜烧结温度以实现陶瓷支架的最佳性能；根据三维仿釉质模型及最佳浆料配方，进行陶瓷支架的结构成型，筛选不同条件下陶瓷支架表面的硅烷化处理，采用树脂真空渗透的方式，在最佳的聚合渗透条件下完成树脂-陶瓷复合材料的最终制备。同时，对该复合陶瓷的三点抗弯曲强度、显微硬度、弹性模量、断裂韧性、摩擦磨损等各项力学性能进行检测，并通过表面形貌和粗糙度检测、XRD、SEM、EDS、EBSD等多种手段分析材料的结构特征，进一步探讨陶瓷材料的力学性能与陶瓷相 (氧化锆相、氧化铝相) 的含量、类型、分布、化学性质和微观结构参数 (如孔隙率、晶粒尺寸和界面组成) 之间的关系。本研究通过调整仿釉质多孔模型的种类 (包括孔隙尺寸与横纵相截面形态) ，改善打印烧结工艺，优化ZTA陶瓷表面处理及树脂真空渗透条件，成功制备出性能与天然牙釉质匹配的仿釉质复合陶瓷，对构建树脂-陶瓷类牙科复合材料的发展具有重要指导意义和科学价值，为牙科陶瓷修复体仿生制备提供临床应用前的理论依据。