首页|期刊导航|中华医学杂志（英文版）|Hardness of resin cement cured under different thickness of lithium disilicate-based ceramic
中华医学杂志（英文版）2011，Vol.124Issue(22)：3762-3767,6.DOI:10.3760/cma.j.issn.0366-6999.2011.22.029
Hardness of resin cement cured under different thickness of lithium disilicate-based ceramic
Hardness of resin cement cured under different thickness of lithium disilicate-based ceramic
摘要
Abstract
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.关键词
lithium disilicate ceramic/polymerization/vickers hardness/thickness/dual-cured resin cement/light-curing timeKey words
lithium disilicate ceramic/polymerization/vickers hardness/thickness/dual-cured resin cement/light-curing time引用本文复制引用
ZHANG Xuan,WANG Fu..Hardness of resin cement cured under different thickness of lithium disilicate-based ceramic[J].中华医学杂志（英文版）,2011,124(22):3762-3767,6.基金项目
This study was supported in part by a grant from the National Natural Science Foundation of China (No.51002185). （No.51002185）
