Occupational nasal carcinogenesis among dentists?

671 dentists were registered in Alberta for 1973. In that year two dentists presented at the Cross Cancer Institute with extensive anaplastic squamous cell carcinoma involving the nasal cavity and accessory sinuses, an incidence rate of 298 per 100,000. Owing to the Provincial Cancer Service the registration of malignant disease is virtually complete and during 1973 the total Alberta registration of squamous carcinoma of the nasal cavity, accessory sinuses and nasopharynx was 28 cases. Assuming that all 28 cases arose in males over 24 years of age, and knowing that the 1973 Alberta population included 412,000 males over the age of 24 years a maximum expected incidence rate of 6.8 per 100,000 would apply to this population group. This paper describes the two dentists referred to above, contrasts the incidence rates previously quoted, discusses the frequency of malignancy among dentists in general and most especially draws attention to the role of inhaled oil droplets produced by high speed air rotor dental drills as a possible occupational carcinogenic hazard in the dental profession. On reviewing the world medical literature no previous report of this hazard has yet been traced. There is no significant risk for dental patients.