Introduction: Traumatic dental injuries (TDIs) present a significant challenge for healthcare professionals. Nurses, often the first point of contact for patients, may lack essential knowledge in dental trauma first aid, as noted in the existing literature. Objective: To assess the knowledge of traumatic dental injuries (TDIs) among undergraduate nursing students before and after a targeted educational intervention. Materials and Methods: This quasi-experimental study evaluated the effectiveness of an educational intervention involving 300 nursing students from two universities in Seville. The educational intervention was led by specialist dentists. A pre-test survey was administered to assess students’ baseline knowledge. The session included a lecture on TDI management, followed by a simulation in which students practiced emergency splinting techniques for referral to a dentist. A post-test survey was then conducted to measure changes in students’ knowledge and attitudes towards dental trauma. Results: Only 25.4% of students had prior training in dental trauma. After the intervention, there was a significant improvement in students’ self-assessed knowledge of first aid for TDIs (p < 0.05). A high percentage of students also reported increased confidence in their ability to reimplant a tooth. Statistical analysis of pre- and post-intervention survey results showed a substantial increase in average scores (p < 0.05). Conclusions: Nursing students initially exhibited limited knowledge in managing dental trauma but demonstrated a positive attitude toward learning this new skill. The targeted educational intervention significantly enhanced their understanding, underscoring the need to incorporate such training into nursing curricula. By improving nursing students’ competence in managing dental injuries, this training can help better preserve dental structures and improve the prognosis for dental trauma cases.