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 tim展开更多
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
目的探讨光固化和化学固化模式对双重固化流动复合树脂聚合能力的影响。方法本研究于2011年12月至2012年3月在南京大学口腔医学院修复实验室完成。将双重固化流动复合树脂核材料A(Luxa Core)、B(Clearfil DC Core)和双重固化树脂水门汀C...目的探讨光固化和化学固化模式对双重固化流动复合树脂聚合能力的影响。方法本研究于2011年12月至2012年3月在南京大学口腔医学院修复实验室完成。将双重固化流动复合树脂核材料A(Luxa Core)、B(Clearfil DC Core)和双重固化树脂水门汀C(DUOLINK)3种材料在光固化和化学固化2种固化模式下各制作5个试件,共制作30个试件。试件固化后0.5、24和120h,分别测量其表面努氏显微硬度以判断聚合度;固化后120h的试件用无水乙醇浸泡24h,再次测量其表面硬度,计算浸泡前后硬度降低百分比值以判断聚合的交联密度。采用单因素方差分析和独立样本t检验对数据进行统计学分析。结果 3种材料在2种固化模式下,硬度值均随测量时间的增加而增大(P<0.05),固化后120h硬度值达到最大;固化后120h的硬度值均是光固化模式的显著高于化学固化模式的[A材料:光固化模式(63.88±3.85)MPa,化学固化模式(39.26±0.89)MPa,P<0.05;B材料:光固化模式(66.94±0.97)MPa,化学固化模式(44.18±1.84)MPa,P<0.05;C材料:光固化模式(64.21±1.07)MPa,化学固化模式(50.69±1.47)MPa,P<0.05]。3种材料固化后120h的硬度值经无水乙醇浸泡24h后均出现显著降低(P<0.05),其中A和B材料在化学固化模式下的硬度降低百分比值显著大于光固化模式下的,而C材料在2种固化模式下的硬度降低百分比值差异无统计学意义[A材料:光固化模式(19.58±1.72)%,化学固化模式(25.18±2.82)%,P<0.05;B材料:光固化模式(17.74±1.75)%,化学固化模式(24.56±1.78)%,P<0.05;C材料:光固化模式(23.10±2.50)%,化学固化模式(23.72±1.65)%,P=0.658]。结论固化模式能够对双重固化流动复合树脂的聚合能力(聚合度和交联密度)产生显著影响。展开更多
目的比较不同光强度对双固化树脂黏接剂与牙本质的黏接强度影响。方法将40颗恒磨牙,暴露咬合面牙本质后随机分为两组,每组20颗牙。DC组用双重固化树脂黏接剂Clearfil DC Bond处理,SE组用光固化树脂黏接剂Clearfil SE Bond处理后,端端对...目的比较不同光强度对双固化树脂黏接剂与牙本质的黏接强度影响。方法将40颗恒磨牙,暴露咬合面牙本质后随机分为两组,每组20颗牙。DC组用双重固化树脂黏接剂Clearfil DC Bond处理,SE组用光固化树脂黏接剂Clearfil SE Bond处理后,端端对接从近中方向光照。将黏接试样沿光照方向切成5片（1 mm/片,L1~5）,再将每片垂直黏接界面切出5个微拉伸样本（1 mm×1 mm）,测试两组黏接强度（m TBS）。结果随着穿透牙本质厚度增加,光强度降低导致黏接强度下降。部分样本在制备时发生界面折断,SE组存留样本L170%,L230%,L3~5为0;DC组L1~5分别为68%,86%,56%,44%和38%。SE组L1~5黏接强度分别为：（13.22±8.64）MPa,（7.49±3.88）MPa,0、0、0 MPa;DC组为：（11.25±4.11）MPa,（9.69±5.07）MPa,（8.13±4.88）MPa,（6.83±3.53）MPa和（5.56±2.95）MPa。两组表面两层黏接强度无统计学差异。结论双固化黏接剂与牙本质的黏接强度随着固化光穿透牙本质深度的增加而降低。展开更多
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 tim
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。
文摘目的探讨光固化和化学固化模式对双重固化流动复合树脂聚合能力的影响。方法本研究于2011年12月至2012年3月在南京大学口腔医学院修复实验室完成。将双重固化流动复合树脂核材料A(Luxa Core)、B(Clearfil DC Core)和双重固化树脂水门汀C(DUOLINK)3种材料在光固化和化学固化2种固化模式下各制作5个试件,共制作30个试件。试件固化后0.5、24和120h,分别测量其表面努氏显微硬度以判断聚合度;固化后120h的试件用无水乙醇浸泡24h,再次测量其表面硬度,计算浸泡前后硬度降低百分比值以判断聚合的交联密度。采用单因素方差分析和独立样本t检验对数据进行统计学分析。结果 3种材料在2种固化模式下,硬度值均随测量时间的增加而增大(P<0.05),固化后120h硬度值达到最大;固化后120h的硬度值均是光固化模式的显著高于化学固化模式的[A材料:光固化模式(63.88±3.85)MPa,化学固化模式(39.26±0.89)MPa,P<0.05;B材料:光固化模式(66.94±0.97)MPa,化学固化模式(44.18±1.84)MPa,P<0.05;C材料:光固化模式(64.21±1.07)MPa,化学固化模式(50.69±1.47)MPa,P<0.05]。3种材料固化后120h的硬度值经无水乙醇浸泡24h后均出现显著降低(P<0.05),其中A和B材料在化学固化模式下的硬度降低百分比值显著大于光固化模式下的,而C材料在2种固化模式下的硬度降低百分比值差异无统计学意义[A材料:光固化模式(19.58±1.72)%,化学固化模式(25.18±2.82)%,P<0.05;B材料:光固化模式(17.74±1.75)%,化学固化模式(24.56±1.78)%,P<0.05;C材料:光固化模式(23.10±2.50)%,化学固化模式(23.72±1.65)%,P=0.658]。结论固化模式能够对双重固化流动复合树脂的聚合能力(聚合度和交联密度)产生显著影响。
文摘目的比较不同光强度对双固化树脂黏接剂与牙本质的黏接强度影响。方法将40颗恒磨牙,暴露咬合面牙本质后随机分为两组,每组20颗牙。DC组用双重固化树脂黏接剂Clearfil DC Bond处理,SE组用光固化树脂黏接剂Clearfil SE Bond处理后,端端对接从近中方向光照。将黏接试样沿光照方向切成5片（1 mm/片,L1~5）,再将每片垂直黏接界面切出5个微拉伸样本（1 mm×1 mm）,测试两组黏接强度（m TBS）。结果随着穿透牙本质厚度增加,光强度降低导致黏接强度下降。部分样本在制备时发生界面折断,SE组存留样本L170%,L230%,L3~5为0;DC组L1~5分别为68%,86%,56%,44%和38%。SE组L1~5黏接强度分别为：（13.22±8.64）MPa,（7.49±3.88）MPa,0、0、0 MPa;DC组为：（11.25±4.11）MPa,（9.69±5.07）MPa,（8.13±4.88）MPa,（6.83±3.53）MPa和（5.56±2.95）MPa。两组表面两层黏接强度无统计学差异。结论双固化黏接剂与牙本质的黏接强度随着固化光穿透牙本质深度的增加而降低。
