Antifungal activity of 4% chlorhexidine and 2% sodium hypochlorite against Candida albicans biofilms.
The purpose of this study was to determine the antifungal efficacy of 4% chlorhexidine (CHX) and 2% sodium hypochlorite (NaOCl) on 24-hour Candida albicans biofilms. Candida albicans biofilms were developed on acrylic resin specimens, which were randomly assigned to 1 of 5 groups (n = 3 per group) exposed to 1 mL of 4% CHX for 2, 4, 6, 8, or 10 minutes. Biofilms in contact with 1 mL of distilled water or 2% NaOCl for 10 minutes were used as positive and negative controls (n = 3 per group), respectively. Specimens were analyzed with confocal laser scanning microscopy and a cell viability assay technique. The biovolume of the live subpopulation of the biofilm was calculated with biofilm image analysis software. Statistically significant differences (P < 0.05) in the biovolume of surviving cells were found among the positive control group and the 4-, 6-, 8-, and 10-minute experimental periods. The biovolumes found after 6-10 minutes of exposure to chlorhexidine were significantly different (P < 0.05) from the biovolume after 2 minutes of exposure. The most effective decrease of the biovolume was found after the use of the negative control (sodium hypochlorite) solution. Exposure to 10 minutes of 2% NaOCl removed fungal cells more effectively than all the experimental groups (P < 0.05). The 4% CHX solution showed an antifungal activity against C albicans biofilms but failed to decrease the biovolume to the levels of 2% NaOCl, which eliminated viable cells more effectively and appeared to be more effective in disrupting the attached biofilms.
Maria Clara Maneira
MC
Gama
Denise Gusmao
DG
de Oliveira
Paulo Mauricio Batista
PM
da Silva
Ronald
R
Ordinola-Zapata
Marco Hungaro
MH
Duarte
Vinicius Carvalho
VC
Porto
D000180:Acrylic Resins; D000935:Antifungal Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects*; D002176:Candida albicans / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D002710:Chlorhexidine / Q000494:pharmacology*; D003764:Dental Materials; D004203:Disinfection / Q000379:methods; D018613:Microscopy, Confocal; D012973:Sodium Hypochlorite / Q000494:pharmacology*
D000180:Acrylic Resins; D000935:Antifungal Agents; D003764:Dental Materials; D012973:Sodium Hypochlorite; D002710:Chlorhexidine
Candida albicans; biofilm; cell viability; chlorhexidine; confocal laser scanning microscopy; sodium hypochlorite