Physicochemical properties, cytotoxicity and penetration into dentinal tubules of sodium hypochlorite with and without surfactants

Hernán Coaguila-Llerena; Isadora Barbieri; Mário Tanomaru-Filho; Renato de Toledo Leonardo; Ana Paula Ramos; Gisele Faria

doi:10.5395/rde.2020.45.e47

Physicochemical properties, cytotoxicity and penetration into dentinal tubules of sodium hypochlorite with and without surfactants

Restor Dent Endod. 2020 Sep 10;45(4):e47. doi: 10.5395/rde.2020.45.e47. eCollection 2020 Nov.

Authors

Hernán Coaguila-Llerena¹, Isadora Barbieri¹, Mário Tanomaru-Filho¹, Renato de Toledo Leonardo¹, Ana Paula Ramos², Gisele Faria¹

Affiliations

¹ Department of Restorative Dentistry, São Paulo State University (UNESP), Araraquara School of Dentistry, Araraquara, SP, Brazil.
² Department of Chemistry, São Paulo University (USP), Ribeirão Preto College of Philosophy Sciences and Letters, Ribeirão Preto, SP, Brazil.

Abstract

Objectives: The aim of this study was to assess the physicochemical properties, cytotoxicity and penetration into dentinal tubules of ChlorCid™ Surf (3% sodium hypochlorite [NaOCl] with surfactant) in comparison to ChlorCid™ (3% NaOCl without surfactant).

Materials and methods: The physicochemical properties evaluated were pH, surface tension, free available chlorine (FAC) and contact angle. Cytotoxicity was evaluated in L929 fibroblasts exposed to the solutions by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and neutral red assays. Assessment of penetration into dentinal tubules was performed by staining single-rooted permanent human teeth with crystal violet (n = 9), which were irrigated with the solutions and analyzed in cervical, middle and apical segments. Data were analyzed by one-way analysis of variance (ANOVA) and Tukey's post-test, 2-way ANOVA and Bonferroni's post-test or t-test (α = 0.05).

Results: ChlorCid™ Surf and ChlorCid™ FAC values were close to those indicated by the manufacturer. ChlorCid™ Surf showed lower surface tension and contact angle on dentin, and higher pH than ChlorCid™ (p < 0.05). The penetration of ChlorCid™ Surf was higher in cervical and middle segments, compared with ChlorCid™ (p < 0.05). There was no difference in irrigant cytotoxicity (p > 0.05).

Conclusions: ChlorCid™ Surf showed lower surface tension, lower contact angle on root canal dentin, higher penetration into dentinal tubules and more alkaline pH, compared with ChlorCid™. However, both solutions showed similar cytotoxicity and FAC content.

Keywords: Dentin permeability; Materials testing; Physicochemical analysis; Sodium hypochlorite; Surface-active agents.