It is possible that gold-containing dental crowns caused an allergic reaction in the mouth of a 64-year-old woman, which developed into a chronic inflammatory disease, lichen planus of the mouth.
Tests showed that the woman was allergic to gold and was advised to replace the crowns. Clinicians should consider factors that may contribute to the development of oral lichenoid lesions when evaluating and managing patients.
“This is the first time that gold dental crowns directly affect the development of lichen planus of the mouth,” wrote lead researcher Dr. Taha Rasool of the University of Miami and colleagues.
The patient was tested for allergies to various heavy metals. The white arrow points to an erythematous papule, which indicates a positive test for sodium gold thiosulfate.
Lichen planus is a chronic disease of the skin and mucous membranes that mainly affects middle-aged patients, but can occur at any age. The exact cause is unknown, but according to the authors, this condition can be considered an immune response characterized by dysregulation of T-cell activation and subsequent inflammation.
In most cases, lesions of lichen planus are purple papules with well-defined borders, which often occur on the distal parts of the upper and lower extremities and the anogenital region. The defining characteristic is Wickham's stripes, which appear as small gray or white dots or lines over the lesions.
Although the origin of lichen planus is not fully understood, it is associated with hepatitis C and contact dermatitis. In addition, metals, including lead and arsenic, can cause inflammatory and allergic reactions that can lead to lichen planus. In previous studies, according to the authors, lichen planus caused by gold was described as the effect of long-term use of gold salts or gold-containing drugs and supplements.
This particular case describes a 64-year-old woman who was referred to clinicians in December 2021 for re-examination for contact dermatitis after developing oral lichen planus. Although she is prone to self-reported allergic reactions to certain medications, she did not see an allergist prior to her implant consultation.
Specifically, her medical history included the likelihood of developing a maculopapular rash on the palms, soles, and chest seven days after starting the antihypertensive drug doxazosin. The woman had similar reactions and lichenoid lesions after taking several antihypertensives, as well as other drugs such as penicillin. In addition, the woman had several crowns and had a history of persistent mucosal irritation, hyperpigmentation, and thickened areas along the gum line, upper and lower teeth.
After developing lichen planus of the mouth, the patient was referred for allergy testing. Many studies have been done and it has been found that she has a positive allergic reaction to gold, in particular gold sodium thiosulfate. For other common allergens and environmental triggers, such as aromatics, the results were negative.
The woman was instructed to apply triamcinolone 0.1% to her mouth and was advised to consult her dentist. On a follow-up visit, tests showed that the metal bases of her crowns contained an increased amount of gold. Further follow-up by the dentist, as well as replacement of crowns, was recommended to reduce persistent irritation.
When lichenoid lesions of the oral cavity are found in a patient, clinicians should consider aggravating factors, including those of dental origin, that may unexpectedly cause immune dysfunction.
The rash of lichen planus in the oral cavity in a woman was most likely the result of prolonged irritation of the mucous membrane from gold dental crowns.