Zaparolli Danilo, Saquy Paulo César, Cruz-Filho Antonio Miranda
Department of Restorative Dentistry, Ribeirão Preto Dental School, USP - University of São Paulo, Ribeirão Preto, SP, Brazil.
Braz Dent J. 2012;23(6):654-8. doi: 10.1590/s0103-64402012000600005.
The aim of this study was to evaluate the effect of irrigation regimens on dentin microhardness at the furcation area of mandibular molars, using sodium hypochlorite and ethylenediaminetetraacetic acid (EDTA), individually and in alternation. The occlusal surface and the roots of 20 non-carious extracted human permanent mandibular molars were cut transversally and discarded. The tooth blocks were embedded in acrylic resin and randomly assigned to 4 groups (n=5) according to the irrigating regimens: 1% NaOCl solution, 17% EDTA solution, 1% NaOCl and 17% EDTA and distilled water (control). Knoop microhardness of dentin at the furcation area was evaluated. Data were analyzed using one-way ANOVA and Tukey's multiple comparison tests (α=0.05). The results of this study indicated that all irrigation solutions, except for distilled water (control), decreased dentin microhardness. EDTA did not show a significant difference with NaOCl/EDTA (p>0.05), but showed a significant difference with NaOCl (p<0.01). EDTA and NaOCl/EDTA showed a maximum decrease in microhardness. The 17% EDTA solution, either alone or in combination with 1% NaOCl reduced significantly dentin microhardness at the furcation area of mandibular molars.
本研究的目的是评估使用次氯酸钠和乙二胺四乙酸（EDTA）单独及交替冲洗对下颌磨牙根分叉区牙本质显微硬度的影响。将20颗无龋的拔除人类恒牙下颌磨牙的咬合面和牙根横向切割并弃用。将牙块嵌入丙烯酸树脂中，并根据冲洗方案随机分为4组（n = 5）：1%次氯酸钠溶液、17% EDTA溶液、1%次氯酸钠和17% EDTA以及蒸馏水（对照组）。评估根分叉区牙本质的努氏显微硬度。使用单因素方差分析和Tukey多重比较检验（α = 0.05）分析数据。本研究结果表明，除蒸馏水（对照组）外，所有冲洗液均降低了牙本质显微硬度。EDTA与次氯酸钠/EDTA相比无显著差异（p>0.05），但与次氯酸钠相比有显著差异（p<0.01）。EDTA和次氯酸钠/EDTA的显微硬度降低最大。17% EDTA溶液单独或与1%次氯酸钠联合使用均显著降低了下颌磨牙根分叉区的牙本质显微硬度。
