Changes in oral functions and speech when using custom-fitted mouthguards: An uncontrolled before-and-after study

Mouthguards are crucial for protecting athletes against orofacial injuries, yet concerns persist regarding their potential impact on oral functions. This study aimed to investigate the effects of sports mouthguards on oral functions and speech over time.

Thirty national rugby players received custom-fitted mouthguards. Questionnaire responses and speech recordings were collected before mouthguard use and at various intervals after using mouthguards: immediately, 1 week, 2 month, and 6 months. Spectrographic analysis was performed to measure voice onset time (VOT) for /p, b, t, d/ phonemes. Questionnaire responses were assessed with Friedman's test, while VOT changes were examined using one-way repeated measure analysis of variance.

Compliance with mouthguard use improved during training and competitions, with consistent wear reported during matches. Over time, speaking difficulties and lisping decreased significantly (p < .001). The perception of nausea improved (p < .001), stabilizing after 1 month (p = .414). Sensations of bulkiness declined (p < .001). Mouth dryness reduced steadily, with no occurrences reported by all players by the end of the study. None of the participants reported bad breath, ulcers, or redness in the mouth. VOT changed immediately after wearing mouthguards (p < .001), gradually regressing toward the baseline, although not completely reaching it. Players held a favorable view of mouthguard use, with comfort and support for mandatory use increasing over time.

Custom-fitted mouthguards do not lead to significant long-term disruptions in oral functions. Athletes generally adapt to mouthguard use, reporting improved comfort and greater support for their use.