Influence of Light Irradiation Technique on Resin Hardness and Polymerization Shrinkage

本研究的目的是确定光固化复合树脂的聚合收缩率与相对固化度之间的相关性，主要研究结果如下：1.光固化复合树脂产品的体积聚合收缩率：光固化复合树脂产品的体积聚合收缩率在光照射后立即使用连续监测的聚合收缩率计系统测量。发现了复合树脂的聚合收缩率与体积变化系数之间的相关性.临床因素对光固化复合树脂体积聚合收缩的影响：遵循1.，使用一些树脂产品来确定临床因素对体积聚合收缩的影响。采用的临床因素包括照射时间、光源尖端与复合树脂的距离、光照强度、复合树脂的体积和复合树脂的颜色。体积聚合收缩系数受基体树脂或基体树脂的用量和聚合度的影响.聚合度和体积聚合收缩率之间的相关性：根据2.，考察了影响复合树脂聚合度的因素。体积聚合收缩率作为相对固化度的参数，受光照条件、光照强度和光照时间的影响。每种复合树脂都有各自的最佳辐照条件，以提高相对聚合度，降低体积聚合收缩系数。在这项研究中使用的技术被发现是一个有用的方法来确定相对聚合度和体积聚合收缩系数之间的相关性。

The purpose of this research was to determine the correlation between the polymerization shrinkage and the relative degree of cure of light cured composite resins, we made some experiments.The findings were as follows:1. The volumetric polymerization shrinkage of light cured composite resin products : The volumetric polymerization shrinkage of light cured composite resin products were measured immediately after light irradiation employed the continuously monitoring dilatometer system. The correlation between the polymerization shrinkage and the coefficient of volumetric changes of composite resins was found.2. Effect of clinical factors on volumetric polymerization shrinkage of light cured composite resins : Followed the findings of 1., some of the resin products were employed to determine the effect of clinical factors on volumetric polymerization shrinkage. Employed clinical factors were irradiation time, distance between the tip end of light source and composite resin, light intensity, volume of composite resins, and color of composite resins. The coefficient of volumetric polymerization shrinkage was effected by the amount and the degree of polymerization of base resin or matrix resin.3. The correlation between the degree of polymerization and the volumetric polymerization shrinkage : Followed the findings of 2., factors affecting on the degree of polymerization of composite resins were examined. Volumetric polymerization shrinkage as parameters of the relative degree of cure was affected by the irradiation conditions, light intensity and irradiation time. Each composite resins had their own optimum irradiation conditions to increase the relative degree of polymerization and to decrease the coefficient of volumetric polymerization shrinkage. The technique used in this research was found to be a useful method to determine the correlation between the relative degree of polymerization and the coefficient of volumetric polymerization shrinkage.