Table 2 Study characteristics of articles regarding concussion and mouthguard use
StudySportStudy DesignDuration (seasons)Study PopulationExposure MeasuresOutcome MeasuresResults
Wisniewski (2004)26FootballPC187 NCAA Division I-A teamsCustom vs non-custom MG useConcussionNo significant difference in incidence of concussions between players wearing custom vs non-custom MGs (95% CI: 0.99 to 1.75)
McNutt (1989)32FootballXS321 high school teams (n = 2470)MG useSport-related injuries56% of all concussions sustained while not wearing MG (p = 0.001)
Garon (1986)35FootballXSn/a20 high school teams (n = 754)MG useConcussion48% of concussions sustained while not wearing MGs
Stenger (1964)13FootballXS51 College teamCustom MG useHead and neck injuries90% of concussions sustained during 1 season were by players who did not wear MGs
Anonymous (1972)38FootballCS11 University teamCustom MG useConcussionNo concussions for MG users vs 2 concussions for non-users
Dorney (1994)36RugbyCR1First grade player (n = 1)MG use (triple-laminated)Concussion and Mandibular FractureNo recurrent concussion symptoms while using triple-laminated pressure moulded mouthguard
Blignaut (1987)34RugbyXS1First team players (n = 321)MG useHead and neck injuriesNo statistically significant differences in concussion rates between wearers and non-wearers of MGs
De Wet (1981)33RugbyXS110 primary schools (10–13 year olds) (n = 150)Custom MG useConcussionNo concussions for MG users, 12% concussions for non-users
Marshall (2005)40RugbyPC1Rugby Union players in Dunedin, New Zealand n = 304Self-report use of MGsConcussionNo evidence of a protective effect of MGs (RR  = 1.62, 95% CI: 0.51 to 5.11)
Barbic (2005)42Football & rugbyCRCT15 Ontario Universities: male football (n = 394), male rugby (n = 129), female rugby (n = 123)WIPSS Brain-Pad MG vs all other MGsConcussionNo significant difference in number of concussions between WIPSS MG use and all other MGs (p = 0.79; OR: 1.06 (95% CI: 0.51 to 1.61)
Finch (2005)43Australian rules footballCRCT123 teams (n = 301)Custom MG vs usual MG behavioursHead/orofacial injuriesConcussions were distributed roughly equally across study arms (underpowered to be able to assess statistically)
Labella (2002)19BasketballPC150 NCAA Division I teamsMG useConcussionNo significant differences in concussion rates (0.35 vs 0.55) or oral soft tissue injury rates (0.69 vs 1.06) between MG users and nonusers, respectively
Benson (2002)39HockeyPC122 CIAU teams (n = 642)Full vs half face shield use, MG useConcussion severity measured by time loss due to injuryHalf shield cohort: MG use: 2.76 sessions lost per concussion (95% CI: 2.14 to 3.55, n = 23 concussions), no MG use: 5.57 sessions lost per concussion (95% CI: 4.40 to 6.95, n = 14 concussions)
Full shield cohort: MG use: 0 time loss (no concussions), no MG use: 1.80 sessions lost per concussion (95% CI: 1.38 to 2.34, n = 2 concussions)
Benson (2005)41HockeyPC1National Hockey League (n = 1033)MG vs no MGConcussion and concussion severityThe risk of concussion for athletes who did not wear a MG was 1.42 times greater than players who wore a MG, but this difference was not statistically significant (95% CI 0.90 to 2.25)
Concussion severity, measured by time loss from competition, was not significantly different between the two cohorts
Symptom severity measured subjectively using the modified McGill ACE symptom scale was significantly greater for athletes not wearing MGs compared with those who did (p<0.01)
Mihalik (2007)37AnyCSn/aAthletes that sustained a sports-related cerebral concussion (n = 180)Self report use of MGsNeurocognitive impairments using ImPACTNo difference in neurocognitive deficits at time of first follow-up assessment (mean 3 days) between MG users and non-users
Takeda (2005)44n/aLabn/aArtificial skull modelMG vs no MGSurface distortions related to bone and acceleration of the headMG use significantly decreased distortion of the mandibular bone and acceleration of the headform compared with no MG (p<0.01)
Hickey (1967)12n/aLabn/a1 male cadaver2 types of MGPressure changes and bone deformation within the skull50% reduction in bone deformation and intracranial pressure amplitude with a MG in place
  • CR, case report; CS, case series; CRCT, cluster-randomised controlled trial; CIAU, Canadian Inter-University Athletics Union; NCAA, National Collegiate Athletic Association; MG, mouthguard; PC, prospective cohort; XS, cross-sectional