Introduction: School teachers are most likely to be involved at the site of the injuries, making their knowledge of emergency management fundamental to the provision of an appropriate care to children and adolescents. Aim of the study: To assess the effectiveness of educational message on the knowledge and practice of school teachers regarding dental trauma. Materials and Methods: Cluster Randomized Controlled Trial. Schools of Beirut were divided into three categories (public, semi private and private). Two-hundred teachers of each category were selected randomly and divided into “Test and Control group”. An educational message, using power point presentation, brochures and posters, was implemented to teachers in test group. Immediate and long term assessment were performed to evaluate the effect of the educational program. Results: Immediately after the implementation of the educational message, there was a significant improvement in the knowledge and practice of teachers of the test group, persisting approximately the same six months later. Conclusion: The implementation of a dental health educational program using more than one modality, proved to be effective in improving the knowledge of school teachers who are the first individuals to face dental trauma in schools. KEY WORDS: Dental trauma, Tooth injuries, School teachers, Knowledge, Educational tools.