Antimicrobial action of chlorhexidine digluconate in self-ligating and conventional metal brackets infected with Streptococcus mutans biofilm

• Published in: Clinical, cosmetic and investigational dentistry Vol. 10; pp. 69 - 74
• Main Authors: Dias, Ana Paula, Paschoal, Marco Aurélio Benini, Diniz, Rafael Soares, Lage, Lucas Meneses, Gonçalves, Letícia Machado
• Format: Journal Article
• Language: English
• Published: New Zealand Dove Medical Press Limited 2018; Taylor & Francis Ltd; Dove Medical Press
• Subjects: Antimicrobial agents; Biofilm; Biofilms; Chlorhexidine; Cyclohexane; Dental surgery; Fluorescence microscopy; Metals (Materials); Microorganisms; Microscopy; Original Research; Orthodontic Brackets; Orthodontics; Phosphates; Streptococcus infections; Streptococcus mutans; Brazil; United States > US; orthodontic brackets; chlorhexidine; biofilm; Streptococcus mutans
• ISSN: 1179-1357; 1179-1357
• DOI: 10.2147/CCIDE.S148700

The objectives of this study were to assess the adherence of biofilms grown over conventional ligature (CL) or self-ligating (SL) metal brackets and their bacterial viability after 0.12% chlorhexidine (CHX) digluconate treatment. The sample consisted of 48 metallic orthodontic brackets divided randomly into two groups: CL (n=24) and SL brackets (n=24). biofilms were grown over the bracket surface (96 h) and treated with CHX (positive control) or 0.9% phosphate-buffered saline (PBS) (negative control) for 1 min each. Quantitative analysis was assessed by colony-forming units, and fluorescence microscopy was performed aiming to illustrate the outcomes. The tests were done in triplicate at three different times (n=9). Data were analyzed using ANOVA and Tukey test ( <0.05). There were significant differences in brackets' biofilm formation, being CL largely colonized compared with SL, which was observed by colony-forming unit counting ( <0.05) and microcopy images. Significant reduction in the viability of was found in both brackets treated with CHX compared to PBS ( <0.05). The antimicrobial activities of CHX were similar for CL and SL brackets ( >0.05). In conclusion, a lower colonization was achieved in SL brackets and biofilms were susceptible to CHX treatment to both studied brackets.