关键词: 次氯酸钠, 依地酸, 显微镜检查, 电子, 扫描透射

Abstract: Objective To assess the efficacy of NaClO irrigation of root canal at different temperatures. Methods Thirty human teeth with single root-canal mandible premolar were instrumented using standard technique, then were divided into 3 groups, carrying on root-canal irrigation. group A: 5.25% NaClO+System B, group B:5.25% NaClO+15% EDTA, group C:5.25% NaClO+System B+15% EDTA. After the teeth root were split, the scanning electron microscope was used to observe the coronal third ,middle third and apical third parts. Results The amount of remaining debris on root canal wall in group C decreased significantly,compared with group A and B. The differences of coronal third and middle third between group A and B, group B and C,group A and C were significant （P<0.05, P<0.01,P<0.05). The difference of apical third between group A and B was no significant （P＞0.05）, but there were significant differences between group A, B and C（P<0.01, P<0.05).The differences of diameters of dentinal tubules of the coronal third,middle third and apical third parts were significant between various groups (P<0.05 or P<0.01).Conclusion The application of 5.25% NaClO after heating united with 15% EDTA can strengthen the effect of root canal cleaning.

Key words: sodium hypochlorite, edetic acid, microscopy, electron, scanning transmission