Study of metal-resin composite for posterior application

对于牙科修复应用，实验性地使用银-锡和银-铟合金颗粒作为填料制备金属-树脂复合材料。评价了实验开发材料的力学性能（弯曲强度和弹性模量）、生物学性能（细胞毒性和抗菌性能）、化学性能（耐腐蚀性）和耐磨性。所研制的金属-树脂复合材料的最高弯曲强度为91.8 MPa的Ag-Sn填充复合材料和91.0 MPa的Ag-In填充复合材料。这些材料的弯曲强度下降时，他们在水中浸泡了很长一段时间或进行热循环，但下降的速度是类似的商业可获得的后复合树脂。虽然金属-树脂复合材料的弯曲强度接近传统的复合材料Resitas，它是没有竞争力的后复合材料。因此，有必要进一步研究，以提高强度。固化后1个月内，金属树脂复合材料的细胞毒性与银汞合金相似或更小。在凝固前，这些材料有一定的抗菌作用，凝固后，抗菌作用消失。实验复合材料显示出很小的电导率，表明其电化学稳定性。银汞合金在腐蚀液中失泽率较低，银汞合金失泽明显。耐磨性测试表明，金属-树脂复合材料的树脂基体丢失，但填料颗粒保留在表面上，保持其抛光表面，表明相对较高的耐磨性。

For dental restorative applications, metal-resin composites were experimentally prepared using silver-tin and silver-indium alloy particles as filler. The mechanical properties (flexural strength and modulus of elasticity), biological properties (cytotoxicity and untimicrobial property), chemical property (corrosion resistance) and wear resistance of the experimentally developed materials were evaluated. The highest flexural strength of the developed metal-resin composites was 91.8 MPa for the Ag-Sn filled composite and 91.0 MPa for Ag-In filled conaposite. The flexural strength of these materials deceased when they were immersed in water for a long time or subjected to thermal cycling, but the rate of the decrease was similar to those of commercially available posterior composite resins. Although the flexural strength of the metal-resin composites was close to conventional composite resitas, it was not competitive to posterior composites. Therefore, a further study is necessary to improve the strengh. The cytotoxicity of the metal-resin composites was similar or less than that of dental amalgam within one month after the setting. Before setting, untimicrobial effect was found on these materials, but disappeared after setting. The experimental composites showed little electric conductivity indicating its electrochemical stability. The rate of tarnish in corrosive solution was lower than that of dental amalgam which showed remarkable tarnish. Wear resistance tests showed that the resin matrix of the metal-resin composite was lost, but the filler particles remained on the surface maintaining their polished surface, indicating relatively high wear resistance.