Hearing of dentists in the long run: a 15-year follow-up study

Abstract

Pure tone audiograms from 68 dentists with a minimum of 10 yr in dental practice were taken in 1973 and a follow-up was carried out in 1988. The aim was to study whether the dental occupation carried a risk for hearing handicap or not. Allowance for age and sex was made by using the presbyacusis values of SPOOR as the reference. At the speech range of frequencies dentists did not differ from the reference. At higher frequencies of 4, 6, and 8 kHz dentists tended to have higher hearing thresholds than expected. At 6 kHz, both male and female dentists had highly significantly greater hearing thresholds than expected by the corresponding references in both the studies. This difference remained essentially similar over the follow-up period, indicating that dental drill noise was insufficient to cause continuous loss of hearing. While mild NIHL was very common and tended to appear earlier in male than in female dentists, there was in the long run no continuous loss of hearing in either sex other than that attributable to the natural development of presbyacusis.