A Comparative Evaluation of Intraradicular Smear Removal Efficacy of 2% Chitosan (Low Molecular Weight), 4% Chitosan Citrate, and 10% Citric Acid when Used as Final Rinse in Irrigation Protocols: A Field Emission Scanning Electron Microscopic Study.

Aim: This study aims to compare the smear layer removal efficacy of 2% chitosan (low molecular weight) (C-LMV), 4% chitosan citrate (CC), and 10% citric acid (CA) when used in specific irrigant protocols.

Materials and Methods: A total of 60 single-rooted maxillary incisors and canines were decoronated, standardized to a root length of 15 mm, and prepared with rotary files up to protaper F3 size. Sodium hypochlorite was used as initial rinse [8 ml]. The samples were divided into experimental (Group III, IV, V, and VI) ( n = 10) and control groups (I - 17% EDTA, II - normal saline) ( n = 5) based on the type of final rinse solution (5 ml) used, that is, 2% C-LMV, 4% C-citrate, 10% CA, and 1% acetic acid. Samples were dehydrated, split buccolingually, gold sputter coated, and examined in field emission scanning electron microscope.

Results: Overall, the Group IV, V, and III presented the least amounts of smear, debris, and erosion among the experimental groups at the apical, middle, and coronal one-thirds of the root canal with a mean value of 1.53 ± 0.42, 1.33 ± 0.42, and 1.60 ± 0.46, respectively, and there was no statistically significant difference ( P > 0.05).

Conclusion: The use of CC as final rinse solution during biomechanical preparation seems promising.