Microbial contamination of orthodontic appliances made of acrylic resin

Patients and professionals involved in dentistry are constantly exposed to potentially pathogenic microorganisms, which may be present in agents such as instruments and equipment, among others. The production of orthodontic appliances, as well as other dentistry work, is carried out in a dental laboratory where there is potential for cross-infection. Nevertheless, studies which evaluate the presence of bacterial contamination of orthodontic appliances after routine procedures in the dental laboratory are not enough. Also, there is no established clinical protocol for infection control of orthodontic appliances before they are installed in the patient. This study aimed at evaluating bacterial contamination of orthodontic appliances and the effectiveness of disinfection with 2% chlorhexidine and 0.12% chlorhexidine. Two microbiological collections were done from 60 orthodontic appliances made of chemically active acrylic resin. The first collection was made before disinfection and the second was done after, in order to evaluate bacterial growth. After analysis, it was found that 85% of sampled devices introduced were contaminated and that disinfection protocol performed with 2% chlorhexidine was effective. Furthermore, the adopted disinfection protocol should have the device soaked in 2% chlorhexidine for 10 min to prevent patient contamination from contaminated orthodontic appliances.