Bacterial contamination of dental handpieces

Clean dry dental handpieces harbour few bacteria, but contamination of the handpiece lumen with salivary bacteria readily occurs in use. Wiping the outside of the handpiece with disinfectant does not eliminate the potential cross-infection risk. Water issuing from dental units is heavily infested with bacteria, some of oral origin, which presumably colonize the water piping of the units. Attempts to reduce this contamination with hydrogen peroxide were only partially successful.