Effect of enzymatic and NaOCl treatments on acrylic roughness and on biofilm accumulation

SUMMARY As denture cleansers should be able toreduce biofilm accumulation without changing theacrylic resin surface structure, this study evaluatedthe effect of denture cleansers on surface roughnessof acrylic resin and on biofilm accumulation. It wasconducted a crossover study of three phases of4 days each and 13 volunteers wore palatal appli-ances containing four specimens of acrylic resin ofknown surface roughness which were extra-orallysubmitted once a day to three groups of separatedtreatments: (i) negative control, (ii) enzymatic com-mercial solution (Ortoform) or (iii) 0AE5% sodiumhypochlorite (NaOCl).The appliances were im-mersed eight times a day in a 20% sucrose solutionto enhance biofilm formation. On morning of thefifthdayofeachphase,theamountofbiofilmformedon the specimens was estimated by the amount ofprotein extracted with alkali and the surface rough-ness of the specimens was again measured. Newpalatal appliances with new specimens were wornby the volunteers in the following phases, but thetreatments werechanged.Theroughnessoftheresinincreased after the treatments (P 0AE05). The data suggest that the roughnessof acrylic resin was not changed by the cleansers, butthe ability to reduce biofilm accumulation dependedon the product used.