Bacterial aerosols in the dental clinic: effect of time, position and typeof treatment

Objectives: The objectives of this study were to investigate changes in the concentration of total bacterial aerosols before, during, and after the wo rking period at different positions within the same multichair dental clini cs. Also to investigate the contribution to total bacterial aerosols, if an y, of the aerosols generated from different types of dental procedures, as well as the environment. Methods: Air sampling using a Slit-to-Agar air sam pler at three positions in a multichair dental clinic, performed three time s per day over a three week period before work, during work and after work. The second part of the study, in another multichair dental clinic, was per formed before working and during three types of dental procedures. Results: The concentration of total bacterial aerosols and Bacillus sp. in air whic h circulated in the dental clinic was lower at the end of the day than at t he beginning. There was no significant change in the concentration of total bacterial aerosols in different positions in the dental clinic or after th e three types of dental treatments. The concentration of Bacillus sp. in ai r not mainly generated during dental procedures and which may come from an environmental source, was reduced. Conclusions: This study suggests that th e proportions of different types of bacteria in air may change before, duri ng and after dental treatment. Preventive measures may need to be institute d to reduce build up of bacterial aerosols in the dental clinic during non- working periods.