Emotion regulation as a mediator between stress and burnout in dental postgraduate students: a South China cross-sectional study

Background: Although clinical stress is linked to burnout among medical trainees, the mechanisms underlying this relationship remain unclear. This study examines how emotion regulation strategies mediate the stress-burnout pathway in clinical postgraduate dental students in South China. Methods: From September to November 2024, a cross-sectional survey was conducted among 315 clinical postgraduate dental students across eight South Chinese institutions. Burnout was assessed using the Maslach Burnout Inventory-Human Services Survey for Medical Personnel, emotion regulation strategies with the Emotion Regulation Questionnaire, and perceived stressors via validated measures. Multivariate regression and mediation analyses were employed to evaluate emotion regulation’s mediating role. Results: Social pressure was the strongest predictor of burnout (β = 3.836, p < 0.001). Emotion regulation strategies exhibited distinct mediation effects: cognitive reappraisal mediated 8.13% (indirect effect = 0.41, 95% CI: 1.14%–18%) and expressive suppression mediated 10.13% (indirect effect = 0.52, 95% CI: 2.57%–20%) of the total stress-burnout effect. Burnout severity was further moderated by advanced academic year (β = 3.307, p = 0.028), low professional identity (β = 6.285, p < 0.001), and emotion regulation strategies (cognitive reappraisal: β = -0.34, p = 0.003; expressive suppression: β = 0.356, p = 0.013). Dose-response relationships were observed between stressors (social stress, clinical workload) and burnout dimensions (r = 0.31–0.53, p < 0.01). Conclusion: Emotion regulation partially mediates the stress-burnout relationship, with social stress and cognitive reappraisal as key intervention targets. Stage-specific strategies and institutional reforms to reduce systemic stressors are essential for improving dental postgraduate well-being.