Microbiological analysis of orthodontic pliers

Abstract

Objective: To evaluate bacterial contamination of orthodontic pliers used in an academic setting. Methods: Thirty-four pliers were selected - 17 band remover pliers and 17 bird beak pliers. The control group was composed of 3 previously autoclaved pliers of each model. After use, the pliers in the experimental group were immersed in 10 ml of brain-heart infusion (BHI) culture medium for 2 minutes, incubated at 37º C for 24 to 48 h and seeded in duplicates in different agar-based solid culture media to detect and identify microbial agents. Results: Microbiological analyses revealed that there was contamination in both types of orthodontic pliers. Several bacteria were detected, predominantly staphylococcus and isolated Gram-positive (G+) cocci. The band remover pliers had a greater contamination rate and mean values of 2.83 x 109 and 6.25 x 109 CFU/ml, with variations according to the type of culture medium. The 139 pliers also had all types of bacteria from the oral microbiota at values that ranged from 1.33 x 108 to 6.93 x 109 CFU/ml. The highest mean value was found in the medium to grow staphylococci, which confirmed, in certain cases, the presence of Staphylococcus aureus, which are not part of the normal oral microbiota but are usually found in the nasal cavity and on the skin. Conclusion: Orthodontic pliers were contaminated as any other dental instrument after use in clinical situations. Therefore, they should undergo sterilization after each use in patients.