Although sports mouthguards provide protection against trauma, dentoalveolar injuries can still occur with the mouthguards in place. This study examined the effect of mouthguard protection in an in vitro model. A simulated maxilla, out of a polymethylmethacrylate (PMMA) arch, containing replaceable resin teeth, was used to assess the performance of different mouthguard designs. "Boil and bite" and custom-fitted mouthguards (ethylene vinyl acetate [EVA]) laminated with hard (poly-vinyl chloride [PVC]) or soft labial intermediate EVA layers were fabricated according to manufacturers' instructions. A steel ram was dropped onto the mouthguards at the maxillary incisor region. Changes in voltage, which were induced by a strain gauge at the back of the upper left incisor, were measured with an amplified voltmeter. Data were analysed by ANOVA at a significance level of 0.05. "Boil and bite" and mouthguards layered with silicone or with small hard PVC inserts of 1.5 mm thickness demonstrated less absorption and differed significantly from the other mouthguard systems (p < 0.05). Bilaminated mouthguards with hard PVC inserts of 0.8 mm, 1.5 mm or 2 mm thickness showed no significant differences to those with 1.5 mm thick (EVA) inserts. The absorption rates amounted to 33 % compared with the unprotected tooth.

The aim of the study was to determine the prevalence of orofacial injuries among German top athletes and their attitudes to mouthguards. A questionnaire was mailed to athletes of 10 German contact sports associations. 64.3 percent (303) of the athletes returned questionnaires. 62 percent (188) of the respondents reported that at some time they wore a mouthguard for sports participation. 47.3% (male: 57.8%, female: 38.3%) of these were currently using one. 50% of the mouthguards were custom made by dentists, and 50% were shop bought (boil-and-bite). 32 percent of the participants had, at some time during their sports career, suffered an orofacial injury. The incidence of fractured anterior upper teeth and completely knocked out teeth for athletes without mouthguards was 7 and 14, respectively. Whereas for athletes wearing mouthguards one fractured tooth was reported. Athletes with mouthguards complained of problems with speaking (19.9%) rather than of breathing (3.4%) and fitting difficulties (4.8%). Boil-and-bite mouthguards caused more fitting problems than custom-made ones. As prevalence of oral injuries in body-contact sports is high, athletes should be advised that custom-made mouthguards offer the greatest comfort, fit, durability, and protection against dental injuries.