Particulate production during orthodontic production laboratory procedures.

Dental technicians are exposed to respirable particles during their everyday work. This study investigated particulate production during dental laboratory procedures. Real-time air sampling of dental laboratory production processes was carried out, including the use of a plaster hopper, trimming study models and the trimming and polishing of removable orthodontic appliances. Respirable dust volumes in mg/m(3) were determined using real-time air sampler and were compared with the Workplace Exposure Limits (WELs) advised by the Control of Substances Harmful to Health regulations. The use of the plaster hopper produced the highest level of respirable dusts, which might exceed the recommended WELs for respirable dusts. Trimming study models and removable orthodontic appliances using suitable ventilation produced levels of respirable dusts, well below the WEL. Suitable ventilation adjacent to the plaster hoppers is advisable in order to reduce any inhalation risk to dental technicians.