Respiratory Findings in Dental Laboratory Technicians in Rasht (North of Iran)

BACKGROUND There are several occupations that can expose people to some air pollutants. Dental technicians are exposed to inorganic dust and chemical vapors when making dental prosthesis that can put them at risk for respiratory problems. This study was performed to assess respiratory dysfunction in a group of dental technicians. MATERIALS AND METHODS This was a cross-sectional study designed to ascertain the prevalence of respiratory disorders in dental laboratory technicians in Rasht, a city located in north of Iran. A Structured questionnaire was adapted according to the European Community Respiratory Health Survey questionnaire and used to elicit information regarding sociodemographic characteristics and medical status of the study participants. The ventilation status, protective measures and direct exposure to materials in the laboratories were directly observed by the observers and subjects underwent respiratory tests and chest x-ray. RESULTS The mean age of dental technicians was 31.31 yrs (range 18-56 years) and 83% were males with a mean dental work experience of 9.04 years. In 54.8% of cases, the work environment did not have air conditioning system. The most common signs and symptoms were cough (38.1%) and wheezing (16.7%). There was a significant correlation between smoking and respiratory signs. Restrictive airway pattern and air trapping were two prevalent findings which were observed in 85.7% and 33.3% of the subjects. Cigarette smoking had a negative effect on FEV1, FEF25%-75%, and TLC causing a significant reduction in all three parameters (p < 0.05). The most prevalent finding was interstitial opacity which was observed in 10 individuals (23.8%). This finding was not significantly associated with age, gender, cigarette smoking, or daily work hours. However, there was a significant statistical association between work experience and interstitial opacity. CONCLUSION The prevalence of respiratory dysfunction and chest x-ray findings were high as in several similar studies. In order to reduce the hazards of respiratory disorders in risky occupations and provide dental workers with technical preventive measures, a more comprehensive study should be conducted throughout the country and further evaluations through biopsy and CT-scan need to be performed in suspicious cases when necessary.