The aim of this study was to analyze dental comorbidities in untreated primary hyperparathyroidism (pHPT). Patients with pHPT subjected to parathyroidectomy (PTX) at Karolinska University Hospital, Stockholm, during 2011-2016 (n = 982) were selected from the Scandinavian Quality Register of Thyroid, Parathyroid and Adrenal surgery and compared to a general population cohort (n = 2944), matched for age and gender. Dental data was obtained from the Swedish Dental Health Registry for the 3 years prior to PTX. The incidence rate ratios (IRRs) of tooth loss by extraction, periodontal interventions, and dental visit rate were analyzed by Poisson regression models. In order to analyze the impact of disease severity, the PHPT cohort was sub-grouped based on preoperative serum levels of ionized calcium (S-Ca 2+ ). The total number of tooth extractions, periodontal interventions, and number of visits were similar in the cohorts. PHPT patients belonging to the quartile with the highest S-Ca 2+ (≥ 1.51 mmol/L) had increased risk for tooth extraction (IRR 1.85; 95% CI 1.39-2.46). Female gender independently amplified the risk (IRR 1.341, P < 0.027). This study indicates an association between pHPT and oral disorders reflected by increased tooth loss by extraction related to high S-Ca 2 . Increased awareness of dental comorbidity in primary hyperparathyroidism may benefit a large group of patients with a common disease through earlier detection and prevention.