The aim of this study was to make a comparative evaluation of three chemical substances for cleaning complete dentures, as regards their efficacy of biofilm removal. The sample consisted of 20 maxillary complete dentures. The dentures were randomly divided into groups according to the chemical cleaning method to be used: Group 1 – water (control), Group 2 – sodium hypochlorite solution, Group 3 – sodium perborate (Corega Tabs®) and Group 4 – 2% chlorhexidine. The groups were evaluated in terms of the quantity of biofilm before and after application of the chemical cleaning method by applying a revealer, and later, analysed by the Denture Hygiene Index (DHI). The results showed that only sodium hypochlorite solution was effective for biofilm removal. There was statistically significant difference among the groups, pointing out greater efficacy of the method used in Group 2 in comparison with Groups 1 and 4. Group 3 did not differ statistically from any other group evaluated. The results allowed to conclude that sodium hypochlorite solution is the most efficient chemical agent for removing biofilm from complete dentures. However, when used alone, all the tested chemical cleaning methods were incapable of eliminating all the biofilm from denture surfaces.
