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VOLUME 21 , ISSUE 2 ( February, 2020 ) > List of Articles


A Comparison of Salivary Mercury Levels in Children with Attention Deficit/Hyperactivity Disorder When Compared to Age-matched Controls: A Case-control Observational Study

Mohammed J Barry, Fatmah Almotawah, Sharat C Pani, Navin A Ingle

Keywords : Attention deficit hyperactivity disorder, Dental amalgam, Mercury, Saliva

Citation Information : Barry MJ, Almotawah F, Pani SC, Ingle NA. A Comparison of Salivary Mercury Levels in Children with Attention Deficit/Hyperactivity Disorder When Compared to Age-matched Controls: A Case-control Observational Study. J Contemp Dent Pract 2020; 21 (2):129-132.

DOI: 10.5005/jp-journals-10024-2747

License: CC BY-NC 4.0

Published Online: 01-06-2020

Copyright Statement:  Copyright © 2020; The Author(s).


Aim: The aim of this study was to compare the level of mercury in the saliva of children with attention deficit/hyperactivity disorder (ADHD) as compared to age- and gender-matched controls in specific age groups. Materials and methods: A case-control observational study design was used. In school children with ADHD and outpatient dental clinics of a university dental hospital, the participants were schoolchildren diagnosed with ADHD studying in the first grade (6–7 years), sixth grade (12–13 years), and ninth grade (15–16 years) and were gender-matched to children without ADHD attending regular classes in school. Ninety children with ADHD comprised the test group while 90 children without ADHD comprised the control group. Results: In this study, we found that children with ADHD had higher levels of salivary mercury than their age- and gender-matched counterparts; however, this difference was significant only in the 6–7 years of age group. The regression model showed a mild positive association between salivary mercury and ADHD; however, the association was not statistically significant. Conclusion: While there is some indication that salivary mercury may be higher in children with ADHD, there is insufficient evidence to establish a definite association between the two. Clinical significance: The study highlights the need to evaluate existing evidence on the role of mercury, especially salivary mercury, in ADHD.

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