The purpose of this study was to determine the extent of mouth protector use, as well as the amount and type of oral trauma associated with and without mouth guard wear in adolescent athletes. Coaches' perceptions and regulations involving the use of mouth protectors also were examined. Interviews were collected from 2470 junior and senior high school football players with all oral trauma being documented, regardless of the sport during which the injury occurred. Nine per cent of all players suffered from some form of oral injury while another 3% reported a loss of consciousness. Seventy-five per cent of the injuries occurred while not wearing mouth guards, and of this total 40% occurred during baseball and basketball. Fifty-six per cent of all concussions were suffered while not wearing mouth guards. Despite the ability of mouth protectors to significantly help reduce oral injuries, trauma related to sports is more prevalent than previously reported. This study supports the recommendation of mandatory mouth guards in baseball and basketball.