Clinical Outcome of Non‐Surgical Endodontic Treatment Performed by Undergraduate Dental Students: A Retrospective Observational Cohort Study

AIM: To evaluate the outcome of pulpectomy, root canal treatment (RCT) and orthograde retreatment in permanent teeth performed by undergraduate dental students and to assess the influence of various variables. METHODOLOGY: Electronic dental health records at the Department of Odontology, University of Copenhagen, Denmark were analysed covering pulpectomy, RCT and orthograde retreatment performed by dental students 2012-2022 and follow-ups until 2025. Patient-, tooth- and treatment-related variables and follow-up periods were monitored. Effective treatment outcome was defined as absence of pain, no or reduced periapical radiolucency. Chi-square was used for comparisons and uni- and multi-variable logistic regression analyses to assess outcome-related factors. Odds ratio (OR) estimates were presented with 95% confidence interval (CI). RESULTS: One thousand four hundred and sixty-six teeth in 1304 individuals were included. Median follow-up was 14.5 months (interquartile range: 7.6-31.7 months). The overall proportion of effective treatment outcome was 89% (92% for pulpectomy, 87% for RCT and 81% for orthograde retreatment). Using RCT as the reference, pulpectomy was associated with lower odds of non-effective outcome (OR:0.61/CI:0.42-0.88). In multivariable analysis, non-smoking, younger age, premolar teeth and longer follow-up periods had lower odds of non-effective treatment (p < 0.05). Indirect compared to direct restoration was associated with lower odds of non-effective treatment (OR:0.29/CI:0.18-0.47), p < 0.001. CONCLUSIONS: Non-surgical endodontic treatments performed by undergraduate dental students showed a high rate of effective treatment outcome. Pulpectomy showed better outcome compared with RCT and orthograde retreatment. Smoking, older age, non-premolar teeth, shorter follow-up periods and direct restorations were associated with higher odds of non-effective treatment. Awareness of these factors may help improve the predictability of endodontic treatment in an undergraduate clinical setting. Taking the retrospective design and study limitations into account, the results should be interpreted with caution.