[Evaluation of blood mercury concentration in two groups of students of Isfahan Dental School]

ABSTRACT

Dental amalgam has been one of the most widely used restorative dental material for over 150 years. Mercury is one of the main elements in dental amalgam composition. Absorption of mercury in human body can cause serious problems such as insomnia, loss of memory, mental depression and inability to concentrate. Widespread use of dental amalgam in dental schools make a lot of mercury vapour, So, evaluation of blood mercury in dental students during their practical courses may be useful. In this study, two groups of dental students were selected. The first group included 25 clinical dental students and the second 25 preclinical dental students. All selected students were non-smokers, non-alcoholics, and neither group hadn't had new amalgam restoration nor had see food for at least a week. Blood samples were prepared from each group. In each sample 4 ml of blood was drawn and mixed with 0.5 ml, 1% EDTA as anticoagulant. The concentration of mercury was determined by cold vapor atomic absorption spectrometry with amalgamation.. The results showed significant differences between total mercury and nonorganic mercury in two mentioned groups but organic mercury had no significant difference. However means were less than 4ng/ml. According to the result of this study working with amalgam in dental school and operative department can increase blood mercury however no toxicity and serious problem for dental students could be observed. Therefore, it seems making a good air conditioned environment for exiting mercury vapor is necessary, especially in operative department. In addition special attention to control of blood mercury is necessary for assistants, staff and professors of dental school because of their permanent presence in environment containing mercury uapour