Comparative evaluation of the effect of 0.2% chitosan with or without passive Ultrasonic activation used as a final rinse On the tubule penetration of epoxy resin Based and bioceramic sealers on radicular Dentin: an in-vitro confocal laser scanning Microscopy study.

Abstract

ABSTRACT Aim and Objectives: To evaluate and compare the tubular penetration of Epoxy resin and Bioceramic sealers following a final rinse of 0.2% Chitosan, with or without Ultrasonic activation using Confocal laser scanning microscopy (CLSM). Study design: Hundred extracted human mandibular premolar teeth were selected, disinfected and decoronated to obtain samples with standardized root length of 14 mm. The samples were prepared with ProTaper Universal rotary files upto F3 (size 30, 0.09 taper) and were randomly divided into two groups of 50 samples each based on irrigating technique used. Group I: 3% NaOCl and 0.2% Chitosan + Conventional Irrigation for 2 minutes. Group II: 3% NaOCl and 0.2% Chitosan + Passive Ultrasonic Irrigation for 1 minute. In both the groups, 5 ml of 3% NaOCl was used as an initial rinse for 1 min followed by 5ml of 0.2% Chitosan as a final rinse for 2 min. Each group was further divided into two subgroups of 25 samples each depending on the type of root canal sealer used. Group IA: Epoxy resin based sealer (AH Plus) Group IB: Bioceramic sealer (Ceraseal) Group IIA: Epoxy resin based sealer (AH Plus) Group IIB: Bioceramic sealer (Ceraseal) viii Fluorescent dye (Rhodamine B isothiocynate) was added to the sealer during manipulation at an approximate ratio of 0.1% (weight). The root canals were obturated with Gutta-percha points and sealer. Teeth were then sealed with Cavit (3M, ESPE) and incubated at 37°C and 100% humidity for a week to simulate clinical conditions. Specimens were sectioned horizontally with a diamond disc at coronal (8mm from apex), middle (5mm from apex) and apical third (2mm from apex) of each root and these sections were categorized as a, b and c respectively. All sections were polished with silicon carbide abrasive paper (25 micro-meter) and specimens were mounted onto glass slides and examined and evaluated for depth of penetration of sealer by using Confocal Laser Scanning Microscopy (CLSM). Results: The mean depth of penetration of Ceraseal was highest when irrigated with Chitosan and PUI (Group IIB=1476.86±37.18) than when using CI (Group IB=1230.60±39.86), with AH Plus however, the mean depth of dentinal tubule penetration was lower as compared to Ceraseal irrespective of the irrigation technique used, Groups IA (1021±34.11) and IIA (1230.18±38.36). In addition, PUI produced greater penetration of AH Plus compared to CI. When the sections of the root were considered, the highest depth of sealer penetration was observed at coronal third (1506.19±34.59) followed by middle third (1223.34±31.40) and least was at the apical third (989.50±19.93) among all the groups. The higher tubule penetration values were observed with the Ceraseal groups in all the sections observed as compared to AH Plus, irrespective of the irrigation technique used. However, when the interactions between the various sealers, activation technique and sections of the tooth was analysed, the mean depth of sealer penetration ix was observed to be the highest for Bioceramic at the coronal third with PUI (1711.88±210.42) and the least was for AH plus at the apical third with CI (810.19±145.19).