1 INTRODUCTION
Dental amalgam is one of the oldest materials used in oral health care [1]. It has been estimated that 75 % of all single tooth restoration are amalgam restoration and that this percentage has remained stable for many years [2].
Dental amalgam fillings are widely used over all the world. Their content has about 40–50% mercury (Hg). Therefore, dental amalgam fillings can lead to various side effects and clinical problems [3].
Mercury Only liquid metal at room temperature. The
potential toxicity of mercury is the main concern regarding
the use of dental amalgam. The use of dental amalgam as a
restorative material has long been a contentious issue
because of its elemental mercury component [4]. Inhalation
and ingestion of mercury from dental amalgam can occur
during placement, polishing, removal of restorations or
during chewing. The daily dose of mercury from dental
fillings, produced by chewing, would appear to amount to
1-2 ?g/adult. The threshold for hazard to health from
air/mercury exposure in the general population is 5 ?g/m2
air, while it is 1 ?g/m2 for children and pregnant women
[5].
Acute inhalation exposure, at high concentrations, may induce respiratory distress including dyspnea , and might cause damage to cardiovascular systems, with increased blood pressure and heart rate. There may also be negative gastrointestinal effects, with abdominal pain and oral