Machnick Tanya K, Torabinejad Mahmoud, Munoz Carlos A, Shabahang Shahrokh
Department of Endodontics, School of Dentistry, Loma Linda University, CA 92350, USA.
J Endod. 2003 Nov;29(11):747-50. doi: 10.1097/00004770-200311000-00015.
The purpose of this study was to evaluate the effect of MTAD on the flexural strength and modulus of elasticity of dentin. Dentin bars were randomly assigned to eight groups treated with various concentrations of NaOCl (5.25%, 2.65%, 1.31%, 0.66%), 17% EDTA, MTAD, saline, or according to a clinical protocol with 1.3% NaOCl and then 5 min of MTAD. Specimens were subjected to flexural strength and modulus of elasticity tests. Two-sample t test (alpha = 0.05) showed no statistically significant differences between various groups except for a reduction in flexural strength for the 2-h MTAD group (p = 0.002) and the EDTA group (p = 0.002). A significant reduction of modulus of elasticity for the 2-h MTAD group (p < 0.001), EDTA group (p < 0.001), and 0.6% NaOCl (p < 0.002) also was noted. There was no significant difference in flexural strength and modulus of elasticity between the dentin bars exposed to saline or MTAD when applied according to the clinical protocol (p > 0.05). These results indicate that MTAD can be used as prescribed for clinical use without affecting the physical properties of the dentin.
本研究的目的是评估MTAD对牙本质弯曲强度和弹性模量的影响。将牙本质条随机分为八组，分别用不同浓度的次氯酸钠（5.25%、2.65%、1.31%、0.66%）、17%乙二胺四乙酸（EDTA）、MTAD、生理盐水处理，或按照临床方案先用1.3%次氯酸钠处理，然后用MTAD处理5分钟。对样本进行弯曲强度和弹性模量测试。双样本t检验（α = 0.05）显示，除2小时MTAD组（p = 0.002）和EDTA组（p = 0.002）的弯曲强度降低外，各组之间无统计学显著差异。还注意到2小时MTAD组（p < 0.001）、EDTA组（p < 0.001）和0.6%次氯酸钠组（p < 0.002）的弹性模量显著降低。按照临床方案应用时，暴露于生理盐水或MTAD的牙本质条之间的弯曲强度和弹性模量无显著差异（p > 0.05）。这些结果表明，MTAD可按规定用于临床，而不影响牙本质的物理性能。
