Noise-induced hearing loss (NIHL) is an occupational hazard to dentists exposed to the noise from high speed drills. This is the conclusion of a study presented at the 101st Annual Meeting of the American Academy of Otolaryngology--Head and Neck Surgery Foundation.
The study, "Noise-Induced Hearing Loss," was prepared by Renata C. Di Francesco, MD, Fabiana Arajuo Sperandio, MD, Tanit Ganz Sanchez, MD, and Marco Aurelio Bottino, MD, otolaryngologists (ear, nose, and throat specialists) from San Paulo, Brazil. The purpose of the study was to evaluate (1) the incidence of NIHL in dentists; (2) the relationship between duration of exposure and severity of hearing loss; and (3) the relation of risk factors (ambient amplified music) and severity of loss.
The research conducted is significant because dentists are daily exposed to drills, which reach 85 to 95 dB most of the time. Moreover, dentists generally do not wear ear protection or undergo periodic audiometric examinations.
Methodology: The team of medical specialists evaluated 896 dentists attending the Seventeenth International Meeting of Odontology (Dentistry) in San Paulo. All the test subjects were evaluated by a questionnaire, ear examination, and tonal audiometry.
Results: Forty percent of the dentists presented some hearing loss, and 87% of the affected ears presented a demonstrable loss in 6,000 Hz. The incidence of hearing loss was related directly to duration of exposure to noise from dental equipment.