This study aims to assess dental residents' perinatal oral health (POH) knowledge and Regulatory Focus Types' (RFT) impact on their knowledge before and after education. A total of 53 dental residents from upstate New York participated from 2019 to 2021. A validated questionnaire collected demographic data, resident's POH knowledge, RFT, and self-reported burnout levels. In the wave 1 cross-sectional setting, 22 residents participated; while in the wave 2 longitudinal setting, 31 residents completed the questionnaire at the baseline and an 1-hour POH lecture. Multiple linear regression assesses factors related to baseline and post-education POH knowledge and burnout, and logistic regression examined factors related to the RFT types (high-on-promotion and high-on-prevention). Overall, 43.40% of the dental residents were high-on-promotion focus, and 47.17% were high-on-prevention focus. Baseline POH knowledge was relatively low, with an average score of 2.57±1.05 out of the maximum score of 5. Residents with high promotion-focus had statistically significant lower scores on the baseline POH (p<0.05), while high prevention-focused residents demonstrated less improvement of POH following perinatal oral health education (p<0.05). Residents who were high on-promotion appeared to have a lower burnout rate (p<0.001). The study revealed that education effectively enhanced POH knowledge among participating dental residents. RFT significantly influenced knowledge improvement, with high promotion-focused residents showing more substantial gains. To encourage adherence to perinatal oral health policies and guidelines among dental practitioners, future educational approach should consider practitioners' RFT to improve knowledge adoption.