Aging of silorane-and methacrylate-based composite resins: effects on color and translucency

目的 比较人工老化对硅氧烷基和甲基丙烯酸基复合树脂颜色和透光性的影响,为临床提供参考.方法 选用3种光固化复合树脂:甲基丙烯酸基复合树脂A (FiltekTM Z350)、B(FiltekTMP60)和硅氧烷基复合树脂C(FiltekTM P90).每种树脂制备10片试样(直径10 mm,厚度1 mm),均分至水储存(37℃,180d)和冷热循环[(5.0±0.5)与(55.0±1.0)℃,10 000次]两种老化方式中.用分光光度比色仪测量老化前后3种树脂在黑、白、灰背景下的明度(L+)、红绿色品(a*)和黄蓝色品(b*),计算色差(△E)、透光性参数(TP)及其改变(△TP).用独立样本t检验比较3种树脂△E、△TP差异以及各树脂老化前后TP差异;用偏相关分析老化前后△L*、△a*、△b*对△E的影响和黑白背景下色品差值的变化对△TP的影响.结果 树脂C水储存(白、灰背景)和冷热循环(3种背景)老化后均出现视觉可辨的色差(△E＞2.75),且均显著大于树脂A、B(P＜0.05).与冷热循环前相比,树脂C冷热循环后TP显著降低(P＜0.05),且△TP显著小于树脂B(P＜0.05).偏相关分析显示:对于树脂B,白背景下冷热循环后AE与△L*和△b*相关(P＜0.05);对于树脂C,白背景和灰背景下水储存后△E均与△b*(P＜0.05)相关,冷热循环后△E均与△L*和△b*相关(P＜0.05),但黑白背景下色品差值的变化与△TP无明显相关(P＞0.05).结论 人工老化后硅氧烷基复合树脂颜色和透光性变化较明显,且与丙烯酸基复合树脂存在差异.Objective To evaluate the color stability and translucency of silorane-based low shrinkage composite after in vitro aging procedures of thermal cycling and water storage respectively,and to compare with those of conventional methacrylate-based posterior composite.Methods Three light-cured composite resins,dimethacrylate-based composite A (FiltekTM Z350),B (FiltekTM P60) and silorane-based composite C (FiltekTM P90),were tested in this study.Ten specimens (10 mm in diameter,1 mm in height) of each composite were prepared.The ten specimens in each group were then divided into two subgroups (n=5).One subgroup underwent thermal cycling [(5.0±0.5) ～(55.0± 1.0) ℃,10 000 cycles] and the other was stored in 37 ℃ distilled water for 180 days.With a spectrophotometer,the CIE L*a*b* parameters of the specimens were tested before and after artificial aging against white,medium grey and black backgrounds,respectively.△E,TP and △TP were calculated and data were analyzed using independent-samples t test and partial analysis (P＜0.05).Results With regard to color stability,silorane-based composite showed color alteration above the clinically acceptable levels (△E＞3.3),and also showed higher △E with a statistically significant difference in comparison with the other composites (B and C)(P＜0.05) after artificial aging.With regard to translucency,composite C showed more alteration compared with composite B (P＜0.05) after thermal cycling.Conclusions It may be concluded that the silorane-based composite underwent greater alteration with regard to color stability and translucency.PubMed中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)中国科学引文数据库(CSCD)10636-6395