目的:观察光照对两种双固化型树脂水门汀聚合性能的影响。方法:分别取双固化型树脂水门汀Clearfil SA Luting(SA)、Panavia-F(PF),按照说明书混合后,充填于模具中。每种材料随机分为两组,每组5个样本,分别进行不光照与光照20s处理。将...目的:观察光照对两种双固化型树脂水门汀聚合性能的影响。方法:分别取双固化型树脂水门汀Clearfil SA Luting(SA)、Panavia-F(PF),按照说明书混合后,充填于模具中。每种材料随机分为两组,每组5个样本,分别进行不光照与光照20s处理。将制备完成的样本即刻置于傅里叶变换红外光谱仪实验仓内的ATR附件上测量其光谱变化,每隔1min测量1次,测定20min。计算并分析两种材料在20min聚合过程中"C=C"转化率的变化情况。结果:在20min观测期内,未光照的两种水门汀的"C=C"转化率均保持为0;两种材料光照组的"C=C"转化率均显著高于未光照组;光照20s后,PF组转化率在20min内基本不变,SA组转化率随时间而增加;每个观测点SA组的转化率均高于PF组,差异有统计学意义(P<0.01)。结论:光照能显著提高双固化型树脂水门汀的"C=C"转化率。同种光照条件下,SA组的固化性能优于PF组。展开更多
Background The lithium disilicate-based ceramic is a newly developed all-ceramic material, which is lithium disilicate-based and could be used for fabricating almost all kinds of restorations. The extent of light atte...Background The lithium disilicate-based ceramic is a newly developed all-ceramic material, which is lithium disilicate-based and could be used for fabricating almost all kinds of restorations. The extent of light attenuation by ceramic material was material-dependent. Ceramic materials with different crystal composition or crystalline content would exhibit distinct light-absorbing characteristics. The aim of this study was to analyze the influence of ceramic thickness and light-curing time on the polymerization of a dual-curing resin luting material with a lithium disilicate-based ceramic. Methods A lithium disilicate-based ceramic was used in this study. The light attenuation caused by ceramic with different thickness was determined using a spectral radiometer. The commercial dual-cured resin cement was light-cured directly or through ceramic discs with different thickness （1, 2 and 3 mm, respectively） for different times （10, 20, 30, 40, 50 and 60 seconds, respectively）. The polymerization efficiency of resin cement was expressed in terms as Vickers hardness （VHN） measured after 24 hours storage. Two-way analysis of variance （ANOVA） and Tukey＇s HSD tests were used to determine differences. Results Intensity of polymerizing light transmitted through ceramic discs was reduced from 584 mW/cm2 to about 216 mW/cm2, 80 mW/cm2 and 52 mW/cm2 at thicknesses of 1 mm, 2 mm and 3 mm, respectively. Resin cement specimens self-cured alone showed significantly lower hardness values. When resin cement was light-cured through ceramic discs with a thickness of 1 mm, 2 mm and 3 mm, no further increasing in hardness values was observed when light-curing time was more than 30 seconds, 40 seconds and 60 seconds, respectively. Conclusions Within the limitation of the present study, ceramic thickness and light-curing time had remarkable influence on the polymerization of dual-cured resin cement. When resin cement is light-cured beneath a lithium disilicate ceramic with different thickness, prolonging light-curing time accordingly may still be necessary to insure complete polymerization.展开更多
文摘目的:观察光照对两种双固化型树脂水门汀聚合性能的影响。方法:分别取双固化型树脂水门汀Clearfil SA Luting(SA)、Panavia-F(PF),按照说明书混合后,充填于模具中。每种材料随机分为两组,每组5个样本,分别进行不光照与光照20s处理。将制备完成的样本即刻置于傅里叶变换红外光谱仪实验仓内的ATR附件上测量其光谱变化,每隔1min测量1次,测定20min。计算并分析两种材料在20min聚合过程中"C=C"转化率的变化情况。结果:在20min观测期内,未光照的两种水门汀的"C=C"转化率均保持为0;两种材料光照组的"C=C"转化率均显著高于未光照组;光照20s后,PF组转化率在20min内基本不变,SA组转化率随时间而增加;每个观测点SA组的转化率均高于PF组,差异有统计学意义(P<0.01)。结论:光照能显著提高双固化型树脂水门汀的"C=C"转化率。同种光照条件下,SA组的固化性能优于PF组。
基金This study was supported in part by a grant from the National Natural Science Foundation of China （No. 51002185）.
文摘Background The lithium disilicate-based ceramic is a newly developed all-ceramic material, which is lithium disilicate-based and could be used for fabricating almost all kinds of restorations. The extent of light attenuation by ceramic material was material-dependent. Ceramic materials with different crystal composition or crystalline content would exhibit distinct light-absorbing characteristics. The aim of this study was to analyze the influence of ceramic thickness and light-curing time on the polymerization of a dual-curing resin luting material with a lithium disilicate-based ceramic. Methods A lithium disilicate-based ceramic was used in this study. The light attenuation caused by ceramic with different thickness was determined using a spectral radiometer. The commercial dual-cured resin cement was light-cured directly or through ceramic discs with different thickness （1, 2 and 3 mm, respectively） for different times （10, 20, 30, 40, 50 and 60 seconds, respectively）. The polymerization efficiency of resin cement was expressed in terms as Vickers hardness （VHN） measured after 24 hours storage. Two-way analysis of variance （ANOVA） and Tukey＇s HSD tests were used to determine differences. Results Intensity of polymerizing light transmitted through ceramic discs was reduced from 584 mW/cm2 to about 216 mW/cm2, 80 mW/cm2 and 52 mW/cm2 at thicknesses of 1 mm, 2 mm and 3 mm, respectively. Resin cement specimens self-cured alone showed significantly lower hardness values. When resin cement was light-cured through ceramic discs with a thickness of 1 mm, 2 mm and 3 mm, no further increasing in hardness values was observed when light-curing time was more than 30 seconds, 40 seconds and 60 seconds, respectively. Conclusions Within the limitation of the present study, ceramic thickness and light-curing time had remarkable influence on the polymerization of dual-cured resin cement. When resin cement is light-cured beneath a lithium disilicate ceramic with different thickness, prolonging light-curing time accordingly may still be necessary to insure complete polymerization.
