Anti-amalgamists have asserted dramatic improvements in mental illness when amalgam fillings are removed. Huggins reported a case of a 17-year-old girl suffering from mental disease who consulted an internist, a psychiatrist, a hospital for testing, an allergist, an osteopath, a cardiologist, a minister, a psychologist, a gynecologist, a chiropractor, and a psychotherapist without improvement. Only after the patient had her amalgam fillings removed and replaced with composite by Dr. Huggins did all symptoms stop, and there was no recurrence for at least ten months . Kidd also reported a patient remembering "feeling 'sad' from about age 6, and had chronic depression until her fillings were removed in her late thirties."  No information on preoperative or postoperative mercury levels or psychological examinations was provided.
Controlled, scientific studies have failed to show a correlation
between amalgam fillings and mental illness. After conducting
psychologic evaluations of 11 patients with "amalgam illness,"
Lindberg et al determined that the symptoms of "amalgam illness"
in these patients were psychosomatic and that past traumatic events
(and not amalgam) were the triggering factor in these patients'
amalgam illnesses . In a study of 587 Swedish twins whose mean
age was 66 years, investigators were unable to find a relationship
between adverse physical or mental health effects and the number
of surfaces of dental amalgam, either between twins or in the
group as a whole, even after controlling for age, gender, education,
and number of remaining teeth .
Dr. Wahl practices dentistry in Wilmington, Delaware. This article was originally published in Quintessence International 32:696-710, 2001, and is reproduced here with the kind permission permission of Quintessence Publishing Co. The author thanks Drs. J. Rodway Mackert, Ivar A. Mjör, and Fred Eichmiller for reading the manuscript and offering several helpful suggestions.