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

The study on fabrication of dental restoration using PMMA-ZrO_2 composites via CAD/CAM

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 4 4 %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 (2 0 2 5 6± 3 0 9)MPa、(4 30± 0 16 )MPa·m1/ 2 、(5 8 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 16min ,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。

Objective To obtain dental restorations by machining PMMA ZrO 2 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.