聚甲基丙烯酸甲酯-氧化锆复合材料经CAD-CAM 制作牙科修复体的研究

目的在牙科 CAD-CAM 系统上加工聚甲基丙烯酸甲酯-氧化锆复合材料得到牙科修复体.方法将氧化锆纳米粉体成型,制备出具有多孔结构的部分烧结体,然后将预聚甲基丙烯酸甲酯渗透入部分烧结体的开孔中,原位聚合,制备出聚甲基丙烯酸甲酯-氧化锆复合材料.测试部分烧结体和复合材料的机械性能与可切削性能.将复合材料在牙科 CAD-CAM 系统上加工,以得到牙科修复体.结果在部分烧结体密度为 71.44% TD 时,复合材料的弯曲强度、断裂韧性、弹性模量和维氏硬度分别为 (202.56±3.09)Mpa、(4.30±0.16)Mpa·m1/2 、(58.71±1.98)Gpa、(3.82±0.34)Gpa.在 CAD-CAM 系统上加工前磨牙冠所需时间约为 16 min,得到的修复体形态生动,无崩裂缺口或微裂纹.结论聚甲基丙烯酸甲酯-氧化锆复合材料机械性能良好,经牙科 CAD-CAM 系统加工能得到牙科修复体.

The study on fabrication of dental restoration using PMMA-ZrO2 composites via CAD/CAM

OBJECTIVE: To obtain dental restorations by machining PMMA-ZrO2 organic-inorganic composites with the dental CAD/CAM system. METHODS: Partially sintered Zirconia compacts (PSZC) were prepared via isostatic pressing and partially sintering, with Zirconia nanopowder as raw materials. PMMA-Zirconia organic-inorganic composites were prepared by vacuum infiltrating the prepolymerized MMA into the PSZC, followed by in-situ polymerization. The mechanical properties and machinability of composites were studied. The composites were machined on the dental CAD/CAM system to obtain dental restoration. RESULTS: At 71.44% TD of PSZC, the composite had a 3-point bending strength of (202.56 +/- 3.09) MPa, fracture toughness of (4.30 +/- 0.16) MPa.m(1/2), elasticity modulus of (58.71 +/- 1.98) GPa, and Vickers hardness of (3.82 +/- 0.34) GPa, respectively. A premolar crown was fabricated by CAD/CAM system in 16 mins, and was verisimilitude, without any cracks. CONCLUSIONS: The composite at 71.44% TD of PSZC has good mechanical properties and dental restorations can be manufactured by PMMA-Zirconia composites via dental CAD/CAM system.