Title	Patients with Amalgam Restorations Are Not at a Significantly Greater Risk for Developing Health Complications Than Those With Composite Restorations
Clinical Question	For a patient with amalgam restorations, will leaving the restoration intact as opposed to replacing it with composite resin result in significant health complications?
Clinical Bottom Line	Patients with amalgam restorations are not at a significantly greater risk for developing health complications than those with composite restorations. This is supported by the findings of two meta-analyses and a review article that show there is no clinical or epidemiological evidence of amalgam restorations contributing to adverse health effects.
Best Evidence
PubMed ID Author / Year Patient Group Study type (level of evidence) 17436982 Aminzadeh/2007 4 clinical trials, 4 observational studies Systematic review and meta-analysis Key results The odds ratio for the risk of multiple sclerosis among amalgam users was 1.24, with a 95% confidence interval of 0.96 to 1.61. This review found a small yet statistically insignificant increase between amalgam users and multiple sclerosis. 11258092 Dodes/2001 Patients with amalgam restorations Narrative review Key results Data shows that adverse health effects are not an issue until absorption of mercury is 20 to 400 times greater than the amount absorbed by the average person with amalgam restorations. Evidence for health complications are largely a result of patients claiming to feel better when restorations are removed, with very little data to support this claim. This analysis reaches the conclusion that there is no research to support the cessation of amalgam restorations. 18947143 Williams/2008 Amalgam Users Editorial and Opinion Key results The presence of amalgam restorations may lead to increased blood levels of mercury, yet these are significantly lower than necessary to cause adverse effects. None of the proposed diseases correlated with amalgam restorations have any clinical evidence to support a link. In fact, there is even less evidence regarding the biological safety of newer materials used for restorations, whereas amalgams have been extensively analyzed.
Evidence Search	("Dental Amalgam/adverse effects"[Mesh]) AND ( "Dental Amalgam/toxicity"[Mesh] )
Comments on The Evidence	These were comprehensive and detailed articles that assessed many individual studies. The systematic review format of these articles means that data is being assessed from a significantly large sample size, allowing for valid conclusions to be made. One drawback of many of the studies is that they did not take into account the size of the amalgam restorations, as a large restoration will obviously release more mercury.
Applicability	These findings are applicable to any patient who has had amalgam restorations done in the past and is concerned about their potential toxicity, as well as for anyone who is concerned about the future placement of amalgam restorations.
Specialty	(Public Health) (Endodontics) (General Dentistry) (Pediatric Dentistry) (Restorative Dentistry) (Interprofessional CATs)
Keywords	Amalgam, Mercury, Fillings, Amalgam Toxicity
ID#	2789
Date of submission	11/25/2014
E-mail	faltys@livemail.uthscsa.edu
Author	David Quaid Faltys
Co-author(s)
Co-author(s) e-mail
Faculty mentor	John D. Rugh, PhD
Faculty mentor e-mail	rugh@uthscsa.edu
Basic Science Rationale (Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?) None available
Comments and Evidence-Based Updates on the CAT (FOR PRACTICING DENTISTS', FACULTY, RESIDENTS and/or STUDENTS COMMENTS ON PUBLISHED CATs) None available