Objective Collect head impact dose data in young athletes, using an instrumented mouthguard validated per NFL specification. Compare theses doses with published concussive head impact data.

Design Prospective, cross-sectional

Setting Calibrate an instrumented mouthguard head impact dosimeter in laboratory on Hybrid III (HIII) dummy. Collect young athlete non-concussive head impacts on playing field using this dosimeter. Compare these doses to published concussion doses from adult American footballers.

Participants Young American footballers and boxers, n=12, ages 10–21. IRB #13–899.

Assessment of risk factors Single head impact doses, signs/symptoms of concussion.

Outcome measures National Football League (NFL) validity specifications for laboratory testing, head kinematics, presence/absence of concussion.

Main results 177 non-concussive head impact doses were identified. Apparent overlap between non-concussive mouthguard doses and published concussion helmet doses from Rowson et al, (2012) was found. Mouthguard dosimeter meets NFL validity specifications set forth by Siegmund & Guskiewicz et al. (2016) up to 123 g and 7320 rad/s².

Conclusions The mouthguard dosimeter meets the NFL laboratory validity specifications. In human tests, 177 non-concussive, asymptomatic head impacts were measured. Young athlete mouthguard-measured head impact doses (up to 62 g, 4470 rad/s²) had apparent overlap with concussion doses reported from adult athletes wearing instrumented helmets. The overlap may be due to individual concussion tolerance variability, differences in dosimeter accuracy, or peak acceleration magnitude being an insufficient concussion metric. Accurate dosimeter monitoring may be useful in the future to limit play once a certain dose is reached, or to identify dangerous impacts that may have not been observed by the caregiver.

Competing interests Bartsch/Samorezov/Benzel/Miele – Cleveland Clinic has entered into an exclusive license agreement with Prevent Biometrics for Intelligent Mouthguard technology on which the Authors (AB, SS, EB, VM) are inventors. AB & SS are also paid consultants of Prevent Biometrics.

AB, EB and VM are – members of Prevent Biometrics’ Scientific Advisory Panel. Under terms of these agreements there is potential for fee-for-service payments, royalties and/or equity arising from commercialization of head impact measurement and/or head impact safety product(s). The conflicts disclosed here are managed by the Cleveland Clinic Conflict Management Board. Complete details can be found at https://my.clevelandclinic.org/ccf/media/files/About/COI.pdf. These authors also receive research support from the National Institutes of Health, Department of Transportation, Cleveland Clinic, Case Western Reserve University and Rawlings Sporting Goods.

Alberts – as of 4/30/2015, Dr. Alberts has reported a financial relationship and may receive future financial benefits from the Cleveland Clinic for inventions or discoveries commercialised through i-COMET Technologies, Inc

Bernick – as of 5/10/2016, Dr. Bernick has reported financial relationships as a paid consultant, speaker or member of an advisory committee for the following companies: Allergan. Dr. Bernick also receives research support from Ultimate Fighting Championship (UFC), Haymon Boxing, Spike TV, Home Box Office Inc. (HBO) and Top Rank Boxing Inc.

Brett – Dr. Brett is an Officer in Prevent Biometrics, and sub-awardee on federally funded grants from Cleveland Clinic.

Figler, Gray, Russman – None.