Cobalt exposure evaluation in dental prostheses production.

Dental laboratory technicians may be exposed to a number of toxic materials including metal alloys that have been identified as potential health hazards. Particularly, alloys, such as vitallium, wisil, duralium and vironite which in dentistry are used in the production of crowns, bridges and dental prostheses. The most common constituents of these prostheses are cobalt (45-70%), chromium (25-30%), molybdenum, silica, nickle, tantalum and other metals in different amounts. The objectives of this paper are to describe the technology related to the production of dental prostheses, evaluating the most hazardous working jobs and reporting results concerning the monitoring of cobalt and chromium in the urine of 31 people employed in five laboratories of Bergamo, Italy, where workplace air monitoring has also been undertaken.