The odontologists are professionals who exert their displayed activities the intense noises, as in the cavity preparation (74,4 the 95,7 dBA), in the drying of the verbal socket (83,7 dBA), etc. These levels can represent a risk to their health. Objective: to analyze the probable effect of the occupational exposition to the noise in the hearing of odontologists and knowledge of the same ones on the risks of the exposition to the noise. Material and Method: transversal study that evaluated the hearing through tonal audiometry threshold and application of questionnaire in 163 odontologists (56.44% women and 43.55% men) of Curitiba. Result: The odontologists had presented age of 19 to 77 years (average of 39,7 years, DP=12,79), time of service of 1 the 53 years (average of 20,15 years, DP=12,58) and hours of working of 2 to 14 daily hours (average of 7,68h, DP=4,82). Auditory alterations of the sensorineural type in 32,51% had been observed odontologists, predominating in the masculine sex; the occurrence of auditory alterations increased with the age and the years of service; the daily hours of working influenced in the hearing, therefore who works 8 daily hours more than acquired more sensorineural auditory alterations of what those that had worked up to 7 hours (Reason of prevalence=1,79, IC 95% 0,09 - 4,44); the noise in the work was perceived as average (49.07%); 96.9% know the effect of the noise and 3.06% only use auricular protectors. Conclusion: the odontologists present induced suggestive auditory alterations of for noise (reason of prevalence=1,79 95% IC 0,09-4,44) when the daily hours of working are greater than 8 hours.