D2.250 - Sensitivity to Dental Materials and Its Clinical Implications: A Retrospective Patch Test Study

Real-world data on the clinical relevance of patch testing (PT) with dental-series allergens remain limited. This study evaluated the clinical characteristics and PT outcomes of patients tested with a dental screening series in a tertiary allergy clinic.

Adult patients (≥18 years) who underwent PT between 2019 and 2025 due to (i) new-onset oral or perioral symptoms following dental procedures, (ii) suspected occupational allergic contact dermatitis among dental healthcare workers (DHWs), or (iii) self-reported metal- or dental material–related complaints prior to dental treatment were retrospectively reviewed. Patients tested solely for non-dental implant evaluation were excluded. Clinical features and PT results were obtained from medical records. Multivariable logistic regression and subgroup analyses were performed to identify factors associated with positive PT reactions.

A total of 108 patients (86 females, 22 males; median age 59 years, range 22–83) were included. Seventy-four patients (68.5%) presented with post-dental oral or perioral symptoms, 30 (27.8%) were evaluated prior to dental procedures due to metal-related complaints, and 4 (3.7%) were DHWs assessed for hand dermatitis. Among post-dental patients, the most common symptoms were painful oral ulcers (55.4%), gingival complaints (12.1%), and oral or tongue burning (12.1%). At least one positive PT reaction was detected in 86.7% of pre-dental patients, 75% of DHWs, and 67.6% of post-dental patients. The most frequent allergens were nickel(II) sulfate hexahydrate (36.1%), sodium tetrachloropalladate(II) (32.4%), and palladium(II) chloride (29.6%). Subgroup analyses revealed distinct exposure-specific sensitization patterns: methacrylates and glutaraldehyde were detected exclusively in DHWs (p<0.001), whereas nickel sensitization was confined to patient groups (p=0.003). Mercury sensitization was significantly more frequent in DHWs (p=0.003). Patients with a history of allergic disease showed significantly higher sensitization rates to palladium, sodium tetrachloropalladate, and copper sulfate. Nickel sensitization was more frequent in females than in males (40.7% vs 18.2%, p=0.050). In multivariable logistic regression analysis, no single factor remained independently associated with PT positivity.

Nickel(II) sulfate and sodium tetrachloropalladate(II) were the most common sensitizers. Distinct sensitization patterns according to exposure type, sex, and allergic disease history highlight the importance of tailored patch testing and individualized dental material selection for both patients and dental professionals.