APPROACHES TO THE DIAGNOSIS OF ALLERGIC REACTIONS TO METALLIC DENTAL CONSTRUCTIONS

Abstract

Introduction. Dental implants are a highly functional replacement for missing teeth; however, in patients with metal hypersensitivity, cases of implant treatment failure may occur. The presence of foreign materials in the oral cavity and paranasal sinuses may also disrupt the balance of the oral microbiota or induce galvanic phenomena. With the increasing use of orthodontic appliances and dental implants, this issue is becoming more prevalent, which determines the relevance of the present study. Objective. To evaluate current approaches to the diagnosis of allergic reactions to metallic dental constructions based on literature data and clinical observations. Materials and Methods. A review of the scientific literature indexed in the PubMed database over the past 5 years was conducted; several clinical cases from our practice are presented as illustrations. Results. The mechanisms underlying metal allergy are diverse; most commonly such reactions occur as type IV delayed hypersensitivity according to the Coombs classification. Metal ions act as haptens that bind to the major histocompatibility complex and peptide complexes, triggering an immune response mediated by T lymphocytes. The diagnosis of allergy to metal components of dental implants should include detailed medical history, immune-based methods assessing cellular involvement, and skin patch testing. In the presented clinical cases, hypersensitivity to metals used in dental constructions was considered a potential cause of patients’ complaints. Case 1. A 45-year-old female presented with impaired nasal breathing, facial swelling, recurrent bronchitis with bronchial obstruction, general weakness, sleep disturbances, anxiety, and headaches. The patient reported inability to wear jewelry due to erythema developing at sites of skin contact with metal. Approximately 8 years earlier, she had a metallic dental bridge installed, and another one was placed 2 years ago, after which her condition significantly worsened. Patch testing revealed increased sensitivity to titanium, nickel, and chromium. Case 2. A 37-year-old male reported recurrent swelling of the upper lip and upper eyelid, as well as erythema, edema, and pruritus of the skin of the upper and lower extremities during the previous year. Skin allergy tests demonstrated sensitization to house dust mites. Two years earlier, the patient had undergone dental implantation, although he did not associate his symptoms with this procedure. Patch testing revealed hypersensitivity to metals. Case 3. A 54-year-old female complained of facial swelling occurring every morning and decreasing by evening, as well as manifestations of stomatitis and tongue numbness during the previous 6 months. Approximately 9 months earlier, a metallic dental bridge had been placed, and about 10 years earlier a dental prosthesis had been installed on the contralateral side. Recommendations included measurement of potential differences in the oral cavity to exclude oral galvanism, patch testing, and consideration of prosthetic replacement. Conclusions. Allergy to metallic dental components represents an important clinical problem. Detailed dental history, computed tomography, and patch testing with metals used in dental constructions play a key role in diagnosis.