A new instrument for mercury vapor evacuation during clinical work with dental amalgam.

Clinical work with dental amalgam, cutting as well as filling and polishing operations, results in an increased level of mercury vapor in the breathing zone of the patient and often also in that of the dentist. The mercury levels can be minimized by the use of a high volume evacuator which is handled by the nurse. Since many dentists cannot count upon continuous chairside assistance during work with dental amalgam a new instrument, combining the functions of a common dental mirror and an evacuator has been developed. The aim of the present work was to evaluate the mercury vapor evacuating capacity of the new instrument. The study was carried out in a model box especially designed for the in vitro tests performed. The amount of mercury in an area representing the patient's breathing zone was recorded directly and indirectly using an equipment based on atomic absorption spectrophotometry. The results revealed that the new instrument has the capacity for substantially reducing the mercury levels during filling, polishing and cutting amalgam. Thereby the short transitory exposure to mercury vapor during certain working moments can be reduced which should be beneficial both to the patient and to the dental staff.