ABSTRACT
Background and objective The main goal of root canal treatment is to eliminate microorganisms from the canal and to prevent re-infection. To achieve these goals, instrumentation must be combined with adequate irrigation and the placement of intracanal medicament. This study aims to compare the effect of different irrigation activation techniques, i.e., passive ultrasonic irrigation (PUI), EndoActivator (EA), and conventional needle irrigation on the penetration of calcium hydroxide (CH), an intracanal medicament into dentinal tubules. Methodology A total of 60 single-rooted extracted human teeth were selected, which were de-coronated to standardize the root length of 12 mm. An access cavity was prepared, and biomechanical preparation was done. The samples were randomly assigned to three experimental groups: Group I received conventional needle irrigation, Group II underwent EA irrigation, and Group III was subjected to PUI. All the samples were filled with CH paste mixed with Rhodamine B dye, and the orifice openings were sealed with Cavit. The samples were stored in an incubator for 24 hours and were subsequently sectioned horizontally at the coronal, middle, and apical thirds using a hard tissue microtome. These were observed under a confocal laser scanning microscope to evaluate the depth of medicament penetration. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 25.0 (IBM Corp., Armonk, NY). The Shapiro-Wilk test was employed to assess normality, while ANOVA and Tukey's post hoc analysis were utilized to determine significance. Results It was observed that the depth of penetration of CH into dentinal tubules was highest in Group III (PUI), followed by Group II (EA irrigation), with the least penetration observed in Group I (conventional needle irrigation). All the groups showed maximum penetration at the coronal third followed by the middle and apical third. Conclusions Passive ultrasonic irrigant activation resulted in more penetration of CH into the dentinal tubules followed by EA irrigant activation.
ABSTRACT
BACKGROUND: The smear layer acts as a physical barrier against penetration of root canal medicaments and sealers, thus compromising the seal leading to microleakage. OBJECTIVES: This study was conducted to evaluate the efficacy of 17% ethylenediaminetetraacetic acid (EDTA), 0.2% chitosan solution, and 0.2% carboxymethyl chitosan (CMC) used as smear layer removing agents in retrograde root canal preparation using scanning electron microscopy (SEM). MATERIALS AND METHODOLOGY: Eighty single-rooted teeth extracted for periodontal reasons were collected for the study. Root canals were prepared and obturated with gutta-percha coated with AH plus resin sealer. Apical 3 mm of each root resected and Class I retrograde preparation carried out using ultrasonic handpiece and ultrasonic retro tips to a depth of 3 mm along the root long axis. In Group 1 (control), normal saline solution alone was used for smear layer removal. In Group II, 17% EDTA, Group III and IV were treated with 5 ml of 0.2% chitosan and 0.2% carboxyl methyl chitosan, respectively, for 3 min. Blinded evaluation of specimens using SEM was performed independently by two operators who registered the amount of the smear layer present on the surface of the canal walls based on the score described by Hülsmann et al. RESULTS: Group I (saline) was least efficient in the removal of the smear layer. Group II (17% EDTA), Group III (0.2% Chitosan), and Group IV (0.2% CMC) efficiently removed the smear layer from the retrograde cavity with mean scores 1.35, 1.60, and 1.35, respectively. Statistically, no significant difference found in Group II (17% EDTA), Group III (0.2% Chitosan), and Group IV (0.2% CMC). CONCLUSIONS: About 0.2% CMC and 0.2% chitosan can be better alternatives to 17% EDTA for smear layer removal due to their biological advantages.
ABSTRACT
AIM: The aim of this in vitro study is to compare the smear layer removal efficacy of different irrigating solutions at the apical third of the root canal. MATERIALS AND METHODS: Forty human single-rooted mandibular premolar teeth were taken and decoronated to standardize the canal length to 14 mm. They were prepared by ProTaper rotary system to an apical preparation of file size F3. Prepared teeth were randomly divided into four groups (n = 10); saline (Group 1; negative control), ethylenediaminetetraacetic acid (Group 2), BioPure MTAD (Group 3), and QMix 2 in 1 (Group 4). After final irrigation with tested irrigants, the teeth were split into two halves longitudinally and observed under a scanning electron microscope (SEM) for the removal of smear layer. The SEM images were then analyzed for the amount of smear layer present using a three score system. STATISTICAL ANALYSIS: Data are analyzed using the Kruskal-Wallis test and Mann-Whitney U-test. RESULTS: Intergroup comparison of groups showed statistically significant difference in the smear layer removal efficacy of irrigants tested. QMix 2 in 1 is most effective in removal of smear layer when compared to other tested irrigants. CONCLUSION: QMix 2 in 1 is the most effective final irrigating solution for smear layer removal.
