In vitro lymphocyte reactivity to heavy metal salts in the diagnosis of oral mucosal hypersensitivity to amalgam restorations.

Abstract

The value of lymphocyte reactivity in the diagnosis of hypersensitivity to amalgam restorations was studied in a group of patients with oral mucosal lesions, and in a control group. Heavy metal salts were added to lymphocyte cultures, and lymphocyte proliferation and levels of IL-2 receptors and interferon-gamma (IFN-gamma) were determined. After addition of mercuric chloride, a statistically significant increase of IFN-gamma was seen in the patient group, indicating a higher reactivity to this metal salt. Mercuric chloride, nickel sulphate, palladium chloride and zinc chloride all stimulated lymphocyte proliferation, but there was no difference between patients and controls. Nine other metal salts tested did not influence the proliferation rate in either group. Mercuric chloride, nickel sulphate, and zinc chloride did not have any effect on the level of IL-2 receptors. Thus, certain functional tests other than crude lymphocyte proliferation may be useful in the diagnosis of amalgam hypersensitivity.