School of Dentistry, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil.
Braz Oral Res. 2010 Jul-Sep;24(3):277-83. doi: 10.1590/s1806-83242010000300004.
The purpose of this study was to evaluate the hydrogenionic potential and electrical conductivity of Portland cements and MTA, as well as the amount of arsenic and calcium released from these materials. In Teflon molds, samples of each material were agitated and added to plastic flasks containing distilled water for 3, 24, 72 and 168 h. The results were analyzed with a Kruskal-Wallis non-parametric test for global comparisons and a Dunn-Tukey test for pairwise comparisons. The results revealed no significant differences in the pH of the materials (p > 0.05). The electrical conductivity of the cements were not statistically different (p > 0.05). White non-structural cement and MTA BIO released the largest amount of calcium ions into solution (p < 0.05), while arsenic release was insignificant in all of the materials (p > 0.05). The results indicated that the physico-chemical properties of Portland cements and MTA were similar. Furthermore, all materials produced an alkaline environment and can be considered safe for clinical use because arsenic was not released. The electrical conductivity and the amount of calcium ions released into solution increased over time.
本研究旨在评估波特兰水泥和 MTA 的氢离子势能和电导率,以及这些材料释放的砷和钙的量。在聚四氟乙烯模具中,将每种材料的样品搅拌并加入含有蒸馏水的塑料瓶中,分别在 3、24、72 和 168 小时后进行分析。采用 Kruskal-Wallis 非参数检验进行总体比较,采用 Dunn-Tukey 检验进行两两比较。结果显示,材料的 pH 值没有显著差异(p > 0.05)。水泥的电导率没有统计学差异(p > 0.05)。白色非结构性水泥和 MTA BIO 向溶液中释放出最大量的钙离子(p < 0.05),而所有材料中的砷释放都不显著(p > 0.05)。结果表明,波特兰水泥和 MTA 的物理化学性质相似。此外,所有材料均产生碱性环境,可安全用于临床,因为未释放出砷。随着时间的推移,电导率和释放到溶液中的钙离子量增加。