Efficacy of three different irrigation techniques in the removal of smear layer and organic debris from root canal wall: A scanning electron microscope study

Abstract Aim Aim of this study was to compare the removal of smear layer and organic debris within the tooth canal among conventional needle irrigation, EndoVac and Endoactivator. Methodology Eighty single-rooted extracted human teeth were prepared with rotary NiTi instrumentation and randomly separated into 4 groups. Twenty teeth were used as positive control (Group 1), irrigated with only saline. Teeth assigned to Group 2 ( n = 20) received irrigation with a conventional syringe and a 30-gauge needle (NaviTip, Ultradent, South Jordan, UT); samples in Group 3 ( n = 20) were rinsed with an irrigation device based on apical negative pressure (EndoVac, Discus Dental, Culver City, CA) and teeth in Group 4 ( n = 20) were treated with a sonic irrigation system (EndoActivator, Dentsply Tulsa Dental, Tulsa, OK, USA). The amount of residual smear layer and debris was evaluated under a scanning electron microscope, and a semi-quantitative score was assigned to each root at the coronal, middle and apical thirds; the chi-square test was used to compare the results of the S.E.M. analysis. Results EndoActivator performed the best cleansing for both smear layer and organic debris in all root canal thirds, followed by EndoVac and conventional irrigation ( p > 0.001). EndoVac and conventional irrigation showed better cleaning in the coronal area, whereas EndoActivator performed an homogeneous cleansing at all levels. Conclusions The EndoVac system and the EndoActivator system demonstrated significantly more efficacy in cleansing root canal walls than conventional needle irrigation

The Effect of Diode Laser on Planktonic Enterococcus faecalis in Infected Root Canals in an Ex Vivo Model

Objective: This study examined the bactericidal effect of diode laser irradiation against intracanal Enterococcus faecalis. Methods and materials: m total of 128 extracted single-rooted and single-canal teeth were treated with ProTaper instruments (Dentsply Maillefer, Ballaigues, Switzerland). A total of 120 root canals were inoculated with E. faecalis for 21 days, and the samples were randomly divided into five groups: Group 1 (n = 24) samples were irrigated with only saline solution (positive controls); Group 2 (n = 24) was treated with only 5.25% sodium hypochlorite; Group 3 (n = 24) was irrigated with saline solutions activated by diode laser; Group 4 (n = 24) was treated with 5.25% sodium hypochlorite activated by diode laser; and Group 5 (n = 24) was irrigated with saline solution with methylene blue dye activated by the diode laser Fox (Sweden & Martina, Padova, Italy); additionally, eight teeth were not contaminated and their canals were irrigated with saline solution and used as a negative control. The Uro-Quick system was used to determine the microbial residual charge. The data were analyzed using Pearson's chi-square test (p 0.001). Conclusions: Evidence indicates that the diode laser was not more effective than sodium hypochlorite in reducing free bacteria