The aim of this cross-sectional study was to evaluate the frequency of dental
allergens and potential co-factors, especially
hypothyroidism, for patients with an intraoral contact
allergy. From 2015 to 2016, patients with confirmed symptoms of an intraoral contact
allergy (study group SG n = 50) were recruited in the dental clinic of the University of Leipzig. The participants of the control group (CG n = 103) were patients without oral diseases or intraoral symptoms of a contact
allergy. For the data collection, a new "
Allergy questionnaire" was developed. Information on
allergies and general diseases were collected. The statistical analysis was carried out with SPSS 23.0. Sensitizations/
allergies to metals and composites were higher in SG compared to CG. Of all study participants (n = 148), 14.2% (n = 21) had a
nickel allergy. In 18% (n = 8) of the SG a
cobalt allergy based on all
metal allergens could be seen. In addition, an association between a
nickel and
cobalt allergy was found.
Hypothyroidism occurred significantly more frequently (p = 0.049) in SG than in CG. Sensitizations and
allergies can occur to metals in
dental alloys.
Hypothyroidism increased the risk of having an
allergy threefold.