RESUMEN
This paper presents noise problems associated with the use of air-turbine drills in dental practice. Two hundred and fifty dentists [male and female] were randomly selected from the faculty of dentistry as well as the dentists who worked private in Tehran. The results indicated that the mean value of sound pressure level produced by the high-speed drills was 69.1 db. Most of the energy from the drills lied in the high frequency range, 6000- 8OOO Hertz. Audiological evaluations showed that the loss of hearing in all age groups and years in dental practice lie in 6000 Hertz which has a positive correlation with the value of sound pressure level in this frequency. The hearing loss in the right ear of women was slightly higher than the left one, while this was not true in men. The hearing loss in the female group was greater than In male group