Abstract
Objective To compare the efficacy of various techniques used for final irrigation on sealer penetration in the apical one-third of curved root canals. Material and Methods. Sixty-five freshly extracted maxillary first molar teeth with mesiobuccal roots having more than 20° of root curvature were used. The root canals were instrumented and randomly divided into four experimental groups and one control group. In the 4 experimental groups, 3 ml of 17% EDTA followed by 3 ml of 5.25% NaOCl was delivered with the use of the following protocols: Group 1: manual dynamic activation (MDA), Group 2: sonic irrigation (SI), Group 3: passive ultrasonic irrigation (PUI), and Group 4: conventional needle irrigation (CI). All teeth were obturated with gutta-percha and AH Plus sealer labeled with fluorescent dye. Transverse sections at 2 mm and 4 mm distance from the root apex were examined with the aid of confocal laser scanning microscopy. Total percentage (%) and maximum depth (μm) of sealer penetration were measured. Results All the experimental groups exhibited significantly higher penetration rates than the control group at both sections (p < 0.05). However, no significant differences were found in the penetration depth and percentage among the four experimental groups evaluated at both sections (p > 0.05). Conclusion PUI, SI, and MDA did not significantly improve sealer penetration in the apical portion of curved root canals when compared to conventional needle irrigation.
Highlights
One of the main objectives of root canal treatment is thorough debridement of the root canal system, eliminating the microorganisms and their metabolic products as well as organic and inorganic substances from the canal space [1]
The presence of the smear layer acts as a barrier that may hinder the penetration of root canal irrigants, medicaments, and/or sealers into the dentinal tubules [4]
While the passive ultrasonic irrigation (PUI), sonic irrigation (SI), and conventional needle irrigation (CI) groups showed significantly less percentage penetration in 2 mm sections as compared to the 4 mm section (p < 0:05), there was no significant difference between sections in the manual dynamic activation (MDA) group (p > 0:05)
Summary
One of the main objectives of root canal treatment is thorough debridement of the root canal system, eliminating the microorganisms and their metabolic products as well as organic and inorganic substances from the canal space [1]. The pulp tissue, dentin debris, bacteria, related irritants, and the smear layer should be removed from the root canal system during the procedure of root canal treatment [2, 3]. The presence of the smear layer acts as a barrier that may hinder the penetration of root canal irrigants, medicaments, and/or sealers into the dentinal tubules [4]. There is some disagreement about whether to remove the smear layer, the general recommendation is that it should be eliminated before obturation [5]. Several reports have noted the effect of smear layer removal on the interaction between the dentin and root filling material [4]. Agitation of irrigants may improve the sealing properties of root canal filling, providing a better seal interface between root filling and canal walls
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
