J Korean Acad Oral Health.  2012 Dec;36(4):297-302.

Mercury exposure from dental amalgam: a 6 month follow-up

• Baek HJ
• Choi YH
• Sakong J
• Lee YE
• Lee HK
• Jin MU
• Song KB

Abstract

OBJECTIVES
Dental amalgam is a widely used filling material for oral cavity. The released mercury vapor from amalgam could have systemic adverse effects potentially. The purpose of this study is to evaluate the relationship between dental amalgam and urinary mercury levels in children during a 6-month timespan.
METHODS
A total of 525 elementary school children participated in this study. Oral examination was carried out from one dentist. Urine samples collected at baseline and at 6 month were analyzed for mercury and creatinine excretion. Additionally, general characteristics of subjects were surveyed by a questionnaire. The statistical analysis was performed using the SPSS 18.0.
RESULTS
Greater amalgam surfaces were associated to higher urinary mercury levels; this tendency was similar at the 6-month observation after the correct baseline data. In the multivariable model, urinary mercury excretion was only associated with amalgam surfaces positively.
CONCLUSIONS
Even a small amount of mercury uptake from dental amalgam has been associated to increase the mercury concentration of urine.

Keyword

Children; Dental amalgam; Mercury; Urine

MeSH Terms

Child
Creatinine
Dental Amalgam
Dentists
Diagnosis, Oral
Follow-Up Studies
Humans
Mouth
Surveys and Questionnaires
Creatinine
Dental Amalgam

Figure

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  Fig. 1 Urinary mercury levels according to number of amalgam surface at 6 month after adjusted of baseline mercury level.

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