Study of metal-resin composite for posterior application

本文以银锡和银铟合金颗粒为填料制备了金属-树脂复合材料。对实验开发材料的力学性能（抗弯强度和弹性模量）、生物性能（细胞毒性和非微生物性能）、化学性能（耐腐蚀性）和耐磨性进行了评价。所研制的金属-树脂复合材料抗弯强度最高，Ag-Sn填充复合材料为91.8 MPa， Ag-In填充复合材料为91.0 MPa。这些材料的抗弯强度在长时间浸泡在水中或经受热循环时下降，但下降的速度与市售的后置复合树脂相似。虽然金属-树脂复合材料的抗弯强度接近传统的复合材料，但与后路复合材料相比，它没有竞争力。因此，需要进一步的研究来提高强度。金属-树脂复合材料在一个月内的细胞毒性与牙汞合金相似或更低。凝固前对这些材料有抑菌作用，凝固后抑菌作用消失。复合材料的电导率较低，表明其具有良好的电化学稳定性。在腐蚀性溶液中的失光率比银汞合金低，具有显著的失光性。耐磨性试验表明，金属-树脂复合材料的树脂基体丢失，但填料颗粒留在表面，表面保持光滑，耐磨性较高。

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.