Comparative In Vitro Study of the Effect of Chlorhexidine and Sodium Hypochlorite on the Colonization of Delayed-Setting Resin by Candida Albicans

Objectives: The aim of this study was to test the efficacy of aseptic solutions based on chlorhexidine, a combination of chlorhexidine and cetylpyridinium chloride, and sodium hypochlorite on the colonization of delayed-setting resins by Candida albicans, and to establish a prosthetic hygiene protocol. Materials and Methods: 100 samples were made from acrylic resin, standardized to 40 mm × 12 mm × 3 mm, and relined with Kerr® FITT late-cure resin. These were contaminated with a solution containing Candida albicans ATCC 10231, then divided into four groups: (group 1 control), (group 2 Chlorhexidine 0.2%), (group 3 Chlorhexidine 0.12% + cetylpyridinium chloride 0.5%) and (group 4 NaOCl 0.5%). After soaking in the aseptic solutions, the number of CFU/mm2 was determined. Results: The results of this experiment demonstrated the sensitivity of Candida albicans to 0.5% sodium hypochlorite, 0.2% chlorhexidine and 0.12% chlorhexidine in combination with cetylpyridinium chloride, as well as to 0.008 CFU/mm2, 0.0226 CFU/mm2 and 0.0372 CFU/mm2, respectively. Conclusion: The 0.12% chlorhexidine formulation combined with 0.05% cetylpyridinium chloride provides the clinical efficacy of chlorhexidine while avoiding adverse effects, and therefore appears to be the best compromise between efficacy and absence of toxicity.