Purpose: Patients with breast cancer may develop dental problems due to treatment. We examined the prevalence of their dental care use and needs, compared the prevalence of use with that of the general population, and examined which factors predict patients' dental care use. Methods: Patients with primary breast cancer completed a questionnaire at 6 and 15 months post-diagnosis. Medical data were retrieved from medical records. The prevalence of dental care use and needs was examined with descriptive analyses. Associations between predictors and dental care use were examined with multivariate analyses. Results: Twenty-one percent of 746 participants visited their dentist at least once in the past three months at 6 months, and 23% at 15 months post-diagnosis. The estimated percentage of women with at least one contact with their dentist in 12 months was low compared to the general female population (31.9% versus 79.5%). One to two percent of the respondents wanted more contact. Having dental care insurance (odds ratio 1.80; 95% CI, 1.08-3.00), chemotherapy (odds ratio 1.93; 95% CI, 1.21-3.06), and clinical distress 6 months post-diagnosis (odds ratio 2.53; 95% CI, 1.70-3.79) predicted use of dental care 9 months later. Conclusions: Up to 15 months post-diagnosis, breast cancer patients' dental care use is lower than warranted. Oncologists and cancer nurses are recommended to inform patients about dental risks, and to encourage them - particularly those without insurance - to visit their dentist. Occurrence of dental problems should be monitored, especially in patients who receive chemotherapy or who are clinically distressed.