Ghasemi Negin, Rahimi Saeed, Shahi Shahriar, Salem Milani Amin, Rezaei Yashar, Nobakht Mahnaz
Dental and Periodontal Research Center, Department of Endodontics, Dental School, Tabriz University of Medical Sciences, Tabriz, Iran.
Department of Endodontics, Dental School, Tabriz University of Medical Sciences, Tabriz, Iran.
Iran Endod J. 2016 Fall;11(4):325-328. doi: 10.22037/iej.2016.13.
The aim of this study was to evaluate the effect of adding propylene glycol (PG) to mineral trioxide aggregate (MTA) liquid with volume ratio of 20% on the compressive strength (CS) of MTA in two time periods (4 and 21 days) after mixing.
Four groups of steel cylinders (=15) with an internal diameter of 3 and a height of 6 mm were prepared and MTA (groups 1 and 2) and MTA+PG (80% MTA liquid+20% PG) (groups 3 and 4) were placed in to the cylinders. In groups 1 and 3 the CS was evaluated after 4 days and in groups 2 and 4 after 21 days. Data were calculated using the two-ways ANOVA. The level of significance was set at 0.05.
The highest (52.22±18.92 MPa) and lowest (4.5±0.67 MPa) of CS was obtained in 21-day MTA samples and 4-day MTA+PG specimen, respectively. The effect of time and PG were significant on the CS (<0.05). Mixing MTA with PG significantly reduced the CS; but passing the time from 4 to 21 days significantly increased the CS.
Considering the limitations of this study, PG had a negative effect on CS of MTA.
本研究的目的是评估在矿物三氧化物凝聚体（MTA）液体中添加体积比为20%的丙二醇（PG）对混合后两个时间段（4天和21天）MTA抗压强度（CS）的影响。
制备四组内径为3mm、高度为6mm的钢质圆柱体（每组15个），并将MTA（第1组和第2组）和MTA+PG（80% MTA液体+20% PG）（第3组和第4组）放入圆柱体中。第1组和第3组在4天后评估抗压强度，第2组和第4组在21天后评估。数据采用双向方差分析计算。显著性水平设定为0.05。
21天的MTA样本抗压强度最高（52.22±18.92 MPa），4天的MTA+PG样本抗压强度最低（4.5±0.67 MPa）。时间和PG对抗压强度有显著影响（P<0.05）。MTA与PG混合显著降低了抗压强度；但从4天到21天，抗压强度显著增加。
考虑到本研究的局限性，PG对MTA的抗压强度有负面影响。
