Metal-Free Prosthodontic Treatment of Periungual Allergic Contact Dermatitis: A Case Report.

Prosthodontic treatments utilize various procedures and materials such as gold, silver, copper, palladium, cobalt, chromium, and titanium to restore oral function; however, these materials are known to induce allergic contact dermatitis (ACD). We present herein a case in which a patient showed improvement in ACD after undergoing prosthetic treatment using metal-free dental materials. A 53-year-old female patient with periungual inflammation was referred to our department due to instability with her maxillary prosthesis, which was attributed to severe peri-implantitis. Skin tests were conducted due to the suspicions of a metal allergy, and patch testing revealed positive reactions to dental metals, specifically cobalt and palladium. As a result of this finding, all of the patient's metal-based prostheses were systematically replaced with provisional crowns. During this period, any teeth and dental implants affected by severe periodontitis were extracted, after which the patient was fitted with zirconia-based prostheses, resulting in a significant reduction in periungual inflammation. In this case, therefore, the utilization of metal-free prostheses facilitated improvement of the patient's ACD, providing valuable insights for dental practitioners managing patients with ACD.