通过软化试验评估交联密度：乙醇浓度的影响。

Cross-link density evaluation through softening tests: effect of ethanol concentration.

作者信息

Schneider Luis Felipe J, Moraes Rafael R, Cavalcante Larissa M, Sinhoreti Mário A C, Correr-Sobrinho Lourenço, Consani Simonides

机构信息

Dental Materials Area, University of Campinas, School of Dentistry, Piracicaba, Brazil.

出版信息

Dent Mater. 2008 Feb;24(2):199-203. doi: 10.1016/j.dental.2007.03.010. Epub 2007 Jun 4.

DOI:10.1016/j.dental.2007.03.010

PMID:17544496

Abstract

OBJECTIVES

The aim of this study was to investigate whether the ethanol concentration used would influence the outcomes obtained through softening tests when comparing light-activation modes.

METHODS

Disc specimens (n=20) of Filtek Z250 and Filtek Z100 (3M ESPE) were light activated by standard (S) and pulse-delay (PD) modes. Initial Knoop hardness (KHN) measurements were performed 24h after dry storage at 37 degrees C. Half of the specimens (n=10) of each resin-composite were stored in absolute ethanol (100%) and the other half in 75% ethanol solution, for 24h at room temperature, and KHN was determined anew. Initial hardness data were submitted to Student's t-test (p=0.05). Percentages of hardness decrease were analyzed by two-way ANOVA followed by pairwise Tukey's test (p=0.05). The statistical analyses were performed separately for each resin-composite.

RESULTS

No statistically significant differences were observed between standard and pulse-delay modes for initial Knoop hardness values. After storage in 75% ethanol solution, KHN was decreased in all cases but no significant differences were detected between light-activation modes (Filtek Z250: PD=12.6%, S=13.5%; Filtek Z100: PD=13.5%, S=11.8%) regardless of the resin-composite tested. After absolute ethanol storage, higher decrease in KHN were observed. Samples light-activated by the PD mode (Filtek Z250=20.4% and Filtek Z100=16.9%) exhibited significantly higher percentage decrease of KHN than specimens light-activated by the standard mode (Filtek Z250=14.1% and Filtek Z100=8.8%), regardless of the resin-composite tested.

CONCLUSION

The ethanol concentration affected the outcomes of the softening test.

摘要

目的

本研究旨在调查在比较光固化模式时，所用乙醇浓度是否会影响通过软化试验获得的结果。

方法

将Filtek Z250和Filtek Z100（3M ESPE）的圆盘样本（n = 20）分别采用标准（S）模式和脉冲延迟（PD）模式进行光固化。在37℃干燥储存24小时后进行初始努氏硬度（KHN）测量。每种树脂复合材料的一半样本（n = 10）在室温下于无水乙醇（100%）中储存24小时，另一半在75%乙醇溶液中储存24小时，之后重新测定KHN。初始硬度数据采用Student's t检验（p = 0.05）。硬度降低百分比通过双向方差分析，随后进行两两Tukey检验（p = 0.05）。对每种树脂复合材料分别进行统计分析。

结果

初始努氏硬度值在标准模式和脉冲延迟模式之间未观察到统计学显著差异。在75%乙醇溶液中储存后，所有情况下KHN均降低，但无论测试的树脂复合材料如何，光固化模式之间均未检测到显著差异（Filtek Z250：PD = 12.6%，S = 13.5%；Filtek Z100：PD = 13.5%，S = 11.8%）。在无水乙醇储存后，观察到KHN有更高程度的降低。无论测试的树脂复合材料如何，采用PD模式光固化的样本（Filtek Z250 = 20.4%，Filtek Z100 = 16.9%）的KHN降低百分比显著高于采用标准模式光固化的样本（Filtek Z250 = 14.1%，Filtek Z100 = 8.8%）。