ZnO介晶填料的制备及其齿科复合树脂的性能

无机填料是齿科修复复合树脂的主要成分, 它对复合树脂的性能和功能至关重要。本文以三乙醇胺为软模板剂, 六水合硝酸锌为主要原料, 水热法制备平均晶粒尺寸37.5 nm ZnO晶粒构筑的微米级多孔介晶微球, 具有良好的有序性。经γ-甲基丙烯酰氧丙基三甲氧基硅烷(γ-MPS)对ZnO介晶微球改性后, 与改性的SiO₂微球混合, 添加到Bis-GMA/TEGDMA树脂体系中, 制成复合树脂。通过形貌和性能测试发现, 20wt% ZnO介晶填充的复合树脂中填料分散均匀、力学和耐磨损性能优异, 其中树脂弯曲强度133 MPa、弯曲模量9.8 GPa; 磨损3000次后, 树脂体积损耗为1.02 mm ³, 磨损量比商业ZnO微球和单纯SiO₂填充的复合树脂分别降低了88.7%和90.8%。而且, 含氧化锌的复合树脂对口腔中变异链球菌的抗菌率达到99.9%。

Preparation of Zinc Oxide Mesocrystal Filler and Its Properties as Dental Composite Resin

The inorganic filler is the main component of the dental restoration composite resin, which is very important for the properties and functions of composite resin. In this paper, zinc oxide (ZnO) mesocrystal microspheres were prepared from Zn(NO₃)?6H₂O solution in presence of triethanolamine as the soft template by hydrothermal method, these microspheres were self-assembled by 37.5 nm ZnO crystallite and with good order. ZnO mesocrystal microspheres were modified with γ-methacryloxypropyl trimethoxysilane (γ-MPS) and subsequently mixed with modified SiO₂ microspheres as fillers, and then added to the Bis-GMA/TEGDMA system to prepare the composite resin. Through morphology observation and performance test, it is found the filler is uniformly dispersed in composite resin. The one filled with 20wt% ZnO mesocrystals has excellent mechanical properties and wear resistance, among which the flexural strength and modulus reach 133 MPa and 9.8 GPa, respectively with the volume loss at 1.02 mm ³ after 3000 times of wearing, which was 88.7% and 90.8% lower than that of the composite resin filled with commercial ZnO microspheres and bare SiO₂, respectively. Moreover, the antibacterial rate of zinc oxide composite resin against streptococcus mutans in the oral cavity reached 99.9%.