Hypersensitivity to Dental Cast Metals: A Clinical Study

Concerns over allergic reactions to dental restorative and orthodontic materials have increased in the past few years. The incidence appears to be quite low, but increases with increased quantity and duration of exposure to a causative antigen. In most instances intraoral allergies result in a type IV, delayed contact response that may manifest in various ways including lichenoid reactions, burning mouth/burning lip syndromes, cheilitis and lip swelling, oral granulomatous reactions, gingival hyperplasia, non-specific erythema and edema, ulceration and gingivitis or even periodontitis. In this paper, hypersensitivity reactions to dental metals are reviewed and allergy to dental cast metal alloys is studied in a group of patients presenting with oral features sometimes associated with contact hypersensitivity reactions. Of 438 patients evaluated, 18 (4.5%) were determined to have mucosal lesions confirmed by clinical appearance, contact with causative restorations, patch testing and biopsy.