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Prevalence of Mercury-Resistant and Antibiotic-Resistant Bacteria found in Dental Amalgam

Author Affiliations

  • 1Department of Biological Sciences, College of Science and Mathematics, MSU-Iligan Institute of Technology, Iligan City, PHILIPPINES

Int. Res. J. Biological Sci., Volume 3, Issue (4), Pages 1-4, April,10 (2014)


Mercury and antibiotic resistance has long been a subject of interest in microbiology that a vast of literature consisting of studies that looked at its genetics and molecular mechanisms. The aim of this study was to isolate and identify Mercury-resistant and antibiotic resistant bacteria and determine the Hg-resistant isolates were also antibiotic resistant. Twenty four bacterial isolates (54% Gram-negative and 46% Gram-positive) from saliva samples with amalgam fillings were screened for Mercury and resistance by cultivation in an HgCl-containing medium. Surviving organisms were identified using the conventional method of identification and susceptibility to antibiotics was determined by Kirby-Bauer disc diffusion. All of the twenty four isolates were able to grow in Mercury-containing medium and were considered as Hg-resistant bacteria. The rate of susceptibility of the bacterial isolates against the antibacterial disk showed high mean percentage in each antibiotic disk, showing that there is a growing trend of susceptibility to antibiotic which might result to antibiotic resistance. The result of the study showed that Mercury-resistant and antibiotic-resistant bacteria can be isolated from the oral saliva samples of the amalgam filled individual. This is a matter of interest for science and medicine since more and more bacterial species acquire genes that confer them resistance and presents new challenges for treating the associated conditions it cause and in eliminating the bacteria themselves.


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