Aim: The purpose of this interventional study was to evaluate the effect of a short dental trauma lecture on knowledge of first-aid management of dental avulsion among high-risk population. Methods: A total of 336 army recruits were randomly assigned to two groups. To evaluate the level of knowledge, we used a structured questionnaire, adapted from Andersson et al. (Dent Traumatol, 22, 2006, 57) and translated to Hebrew. The control group (n = 137) answered the questionnaire. The intervention group (n = 199) received a 60-min slides lecture by a (military) dental practitioner, regarding general concepts of body injuries, facial and oral injuries and practise first-aid management of these injuries. The intervention group filled the same questionnaire following this lecture. Results: General knowledge of emergency treatment of injuries to other parts of the body was rather good for all participants; however, the level of knowledge was significantly higher in the intervention group (P < 0.05). General knowledge regarding tooth and avulsion was quite disappointing in the control group but was significantly higher in the intervention group (P < 0.001). The same was observed when interpreting the results regarding special knowledge of avulsion first-aid management: How to clean the tooth before replantation, extra-alveolar time and storage method and medium (P < 0.001). Conclusions: The present study revealed excellent results following a short dental trauma instruction lecture. As raising the public awareness on the subject of dealing with dental trauma is important for the prognosis of the tooth, this way of improving knowledge to high-risk populations should be further examined in long-term studies.