Suspected dental amalgam-triggered oral lichen planus occurs when oral lichenoid lesions are topographically in close proximity to the dental amalgam. Patch testing can support this diagnosis. Common metals to test include palladium, gold, mercury, tin, copper, nickel, and amalgam powder. A recent a...

Agree with Dr. @Bruce Brod that in oral lichenoid lesion(s) in immediate proximity to an amalgam filling, a positive patch test to mercury, copper, tin, or zinc is supportive but cannot prove causation.More patients with a positive patch test will clear within 3-16 months of amalgam removal than tho...