How Mouthguards Reduce Concussion Risk: What the Evidence Actually Shows
The mechanism, in plain terms — for parents, coaches, and athletic directors deciding what actually protects an athlete's brain.
Your kid takes a hit and pops right back up. You tell yourself the helmet did its job. Here's what nobody says at the equipment table: the helmet protects the skull, the mouthguard protects the teeth — and neither one was built for the thing you actually lie awake worrying about.
Dr. Michael Hutchison noticed the same gap watching his own son play tackle football. He's a dentist. He knew the mouthguard in his son's mouth was designed around a rule written in 1962 — protect the teeth. So he went looking for the one designed to protect the brain. It didn't exist, so he built it, then ran the research to find out whether it worked.
No mouthguard "prevents" concussions, and we'll never tell you one does. But concussions come from the head accelerating too fast — especially rotating — and the lower jaw is a lever straight into the base of the skull. Stabilize that jaw and the evidence points one direction: less of that force reaches the brain, and athletes hold their reaction time better — partly because a stable jaw also lets them breathe and keeps the guard in their mouth.
Upper-teeth mouthguards protect teeth. NeuroGuard+ stabilizes the mandible to address the impact-force pathway that reaches the brain.
The one sentence behind everything on this page.The hit that hurts the brain isn't the one you see. It's the spin.
A concussion isn't a bruise on the skull. It's the brain twisting and sloshing inside it. The force that does the most damage is rotational — the head snapping or rotating — because that's what strains brain tissue the most10. A clean, straight-on hit is survivable in ways a glancing, twisting one isn't. That's why two hits that look identical on film can end completely differently.
So the real question for any piece of protective gear isn't "does it pad the skull." It's "does it reduce how fast the head accelerates and rotates when it gets hit." Helmets do some of that. Almost nothing in an athlete's mouth was ever designed to.
The lower jaw is a lever into the skull. Control it, and less force gets through.
Your lower jaw hinges directly against the base of your skull. When it's loose, a blow to the chin or jaw drives that hinge straight into the skull base — one of the cleanest paths force has to reach the brain. When the jaw is held in a stable position, that pathway changes: the joint can't slam home the same way, and the surrounding muscle absorbs and spreads the load instead of funneling it11. Three things happen when a real lower-jaw appliance is in place during contact:
The jaw stays put
A stabilized lower jaw can't roll forward or back into the skull joint, closing off one of the main routes force takes to the brain.
Force gets spread, not punched through
Real material thickness across the back teeth distributes the load instead of concentrating it at a single point.
The airway stays open
A forward, stable jaw keeps the airway behind the tongue open, so the athlete stays composed through contact instead of fighting for air.
This is the part the dental-protection mindset misses entirely. A guard built to keep teeth in place doesn't have to do any of this. A guard built around jaw position does.
The proof: 412 players, two kinds of mouthguard, one season
This is the study that turns the theory into a number. Two researchers put 220 high school football players in custom mouthguards (3+ mm thick, pressure-laminated) and 192 in over-the-counter ones — the boil-and-bite kind you grab at Dick's. Same six teams. Same helmets. Same season.
Here's what they found2:
- Custom guards (3.5 mm avg thickness): 3.6% concussion rate (8 of 220 players)
- Boil-and-bite (1.34 mm at injury, chewed down from 1.65 mm): 8.3% concussion rate (16 of 192 players)
- Statistical significance: p=0.0423
That's a 2.3× difference — same sport, same hits, different mouthguard. Thickness and fit aren't a luxury. They're the whole game. Two athletes wearing "a mouthguard" on the same field can have very different outcomes, because one is wearing a fitted, full-thickness device and the other is wearing a chewed-down stub.
See the larger cohort behind this (and the disclosure that comes with it)
There's a bigger dataset, too. From 2003 to 2018, researchers tracked 4,010 athletes wearing a custom lower-jaw appliance designed to hold the mandible in a precise rest position; the cohort-wide concussion rate was 0.224%3. One high school team split its roster — half in the device, half in standard guards — and saw 1 concussion among 86 device-wearers versus 13 among 84 controls.
The honest caveat: the lead author of that study also invented the device, and we tell you that every time we cite it. The direction still matches the independent 2014 trial2 and the 2023 meta-analysis1 — studies with no inventor relationship at all.
It's not just fewer hits. It's a faster brain after them.
Here's the finding that doesn't get talked about enough. Repeated head impacts measurably slow the brain down — even when no one gets "concussed." After a bout of routine head contact, researchers can measure increased inhibition in the brain's motor pathways and slower, less accurate reaction times12. That's the sub-concussive cost: not a diagnosis, just a brain working a little worse than it did an hour ago.
Now the part that matters for the lower-jaw approach. When researchers tested a custom mandibular mouthguard head-to-head, the athletes wearing it didn't just take less force — they were protected from that acute slowdown. The mandibular device reduced head acceleration and blunted the electrophysiological and cognitive changes that normally follow head contact13. Less force in, and a brain that holds its reaction time better afterward.
That's the through-line of this whole page. You can't promise a parent their kid won't get a concussion. But you can point at a consistent direction in the evidence: stabilize the lower jaw, and acceleration drops while reaction time holds.
Breathing and fit aren't comfort features. They're why it works in a real game.
The best mouthguard in the world does nothing in the equipment bag. Protection only counts if the athlete actually keeps it in — through four quarters, while talking to a coach, while gassed in the third period. That's the single biggest reason retail mouthguards underperform their lab numbers: they come out.
A stable lower-jaw appliance helps on both fronts. It holds the airway behind the tongue more open under exertion, so breathing stays efficient67 — and an athlete who can breathe and talk doesn't yank the guard out every other play. Comfort drives compliance, and compliance is what turns a lab result into a real-game result. A $20 boil-and-bite that gets spat out the moment it's inconvenient isn't protecting anyone in the moment that counts.
If you want the airway and performance side in more depth, we have a separate page: Jaw Alignment and Athletic Performance.
So what do you actually look for? Fit, thickness, and whether they'll keep it in.
Here's the sentence the whole page builds toward: the protective effect only holds if the mouthguard is custom-fitted with adequate thickness at the back teeth. That's the one variable separating a mouthguard that does the job from one your kid loses interest in by week three. When you're evaluating any device — ours or anyone's — those are the three questions: Is it custom-fitted? Is it thick enough where the force concentrates? Will the athlete actually keep it in?
NeuroGuard+ is engineered around exactly those three: a lower-jaw appliance built from a dental impression, pressure-laminated to the thickness the protective research points to, with retention that survives contact, talking, and chewing. A retail boil-and-bite isn't held to any of that — not by the maker, not by the league, not by the kid chewing on it at practice. That gap is the whole difference between a referee's checkbox and a brain-protection appliance. The orofacial-injury research reaches the same fit-quality conclusion in its own domain9.
"Is this actually proven?"
Not the way a drug is — and any brand that tells you otherwise is overselling. The most-cited skeptical review is from 2011, and the evidence genuinely was thin back then5. But every study since has pointed the same direction: stabilize the jaw, and head acceleration drops while reaction time holds. The picture has moved, and it's moved one way.
If you want the full courtroom — every meta-analysis, every counter-study, and a side-by-side of what's peer-reviewed versus what's marketing — we put it all on one page: the mouthguard concussion research evidence map. We'd rather hand you the whole file than cherry-pick the flattering half.
Why a dentist built a brain-protection appliance
"I'm a dentist, and I'm a dad. I spent years fitting mouthguards built to save teeth, then watched my own son take hits at tackle-football practice and realized not one of them was built for the thing I was actually afraid of. So I built the lower-jaw appliance this page is about — and I put it through the same research I'd want to see before I trusted it with my own kid."
"If you take one thing from this page: the mouthguard your athlete already wears is doing a job. Make sure it's the right job. Is it fitted? Is it thick enough at the back teeth? Will they actually keep it in? That's the line between a checkbox for the referee and protection that does something."
— Dr. Michael Hutchison, Founder, NeuroGuard+ · inventor of the mandibular appliance studied in the 2018 cohort of 4,010 athletes
The bottom line
The question was never "mouthguard or no mouthguard." It's "$20 dental shield from a sporting goods store, or a custom lower-jaw appliance built around the mechanisms the research actually points to." Custom-fitted guards at adequate thickness are associated with concussion rates 2-3× lower than over-the-counter ones2, and the broader meta-analytic figure — a 26% reduction in collision sports1 — points the same way. The research lives in the second category. NeuroGuard+ is in the second category.
Want a side-by-side of how NG+ compares to the most-searched concussion-protection alternatives? See NG+ vs concussion competitors.
The full evidence, if you want to go deeper
Everything above is the short version. Below is the long one — the mechanism detail and every study with its sample size. Open what you want; skip the rest. The full counter-evidence and the vendor scorecard live on the evidence map.
The thickness math — why ≥3 mm at the back teeth is the line
The 1964 cephalometric work that started this conversation X-rayed players hitting blocking sleds with and without thick guards: with ≥3-4 mm of material between the arches, the jaw couldn't slam into the skull base the same way. The 2014 RCT tested it directly — custom guards averaged 3.50 mm posterior thickness; OTC guards 1.65 mm at season start, 1.34 mm by the time injuries happened2. Material thickness is the most controllable variable in the equation, and a retail guard isn't held to it — not by the maker, the league, or the athlete chewing on it during practice.
Neck strength: the other lever a coach can pull
A 2014 study of 6,704 high school athletes found that every 1-pound increase in neck strength dropped concussion odds by 5%8. The jaw connects through the cervical chain to the neck, so a stabilized jaw and a stronger neck pull in the same direction. NG+ isn't a substitute for neck work — it's a complement to it.
Every study, in one table
Every row is a real peer-reviewed study with the original sample size. The meta-analysis (top row) is the strongest single number; the trials and cohorts beneath it support the same direction; the 2011 review at the bottom is the counter-evidence — older, and the literature the more recent meta-analysis updated.
| Outcome | Effect | Source & population |
|---|---|---|
| Concussion incidence (mouthguards in collision sports) | 26% reduction (IRR 0.74, 95% CI 0.64-0.89)1 | Eliason 2023 systematic review and meta-analysis — 192 studies pooled |
| Custom vs OTC, HS football | 3.6% vs 8.3% (p=0.0423)2 | Winters & DeMont 2014 — N=412 HS football, randomized |
| Custom MPRP cohort, 2003-2018 | 0.224% concussion rate (9 of 4,010)3 | Hutchison 2018 — retrospective cohort, inventor disclosed |
| Custom mandibular orthotic, pre vs post | 2.1 ± 1.4 vs 0.11 ± 0.3 events; OR 38.33 (CI 8.2-178.6)4 | Singh 2009 — N=28, retrospective |
| Head acceleration reduced + acute cognitive change prevented (custom mandibular MG) | Significant reduction in peak head acceleration13 | Pitteu 2025 — crossover, amateur soccer players |
| Concussion odds per 1-lb neck strength increase | 5% reduction8 | Collins 2014 — N=6,704 HS athletes |
| Counter-evidence (older review) | "no evidence" of incidence reduction5 | Daneshvar 2011 — systematic review |
What we will and won't claim
Mouthguards do not "prevent" concussions, and we will never put that word on this site. They're associated with reduced incidence in collision sports1 — that's the language the data supports, and the language the FTC has spent years suing manufacturers for avoiding. What we will say: NG+ is engineered around the jaw-stabilization, force-dissipation, and airway mechanisms the research links to lower acceleration and preserved function; the effect is real, fit-dependent, and strongest for custom devices; and equipment is one layer alongside neck strengthening8, helmet quality, rule compliance, and concussion-management protocols. Any brand selling a single device as a "concussion prevention" product is claiming more than the evidence supports. We're not that brand.
FAQs
Do mouthguards actually reduce concussion risk?
The honest answer: they're associated with reduced risk, and you can't promise prevention. A 2023 meta-analysis of 192 studies found mouthguards in collision sports linked to a 26% reduction in concussion incidence (IRR 0.74, 95% CI 0.64-0.89)1. More important for how NG+ works: research on custom mandibular mouthguards shows they reduce head acceleration and help blunt the acute drop in reaction time that follows head contact13. No equipment eliminates risk in any single collision — but the direction of the evidence is consistent.
Why does a lower-jaw mouthguard matter more than a regular one?
Because the lower jaw is a lever into the base of the skull, and concussions are driven by acceleration — especially rotation10. A guard built only to protect teeth doesn't address that pathway. A guard built to stabilize the mandible does: it changes how force transmits into the skull and helps the surrounding muscle absorb the load11. That's the mechanism the strongest research targets.
Will it preserve my athlete's reaction time?
Research points that way. Repeated head impacts measurably increase inhibition in the brain's motor pathways and slow reaction time, even without a diagnosed concussion12. When a custom mandibular mouthguard was tested, athletes wearing it were protected from much of that acute slowdown alongside the reduction in head acceleration13. It's a directional finding, not a guarantee — but it's the reason the lower-jaw approach is interesting beyond dental protection.
Why are custom mouthguards more protective than boil-and-bite?
Fit, thickness, and compliance. A 2014 trial of 412 high school football players found custom guards (≈3.5 mm thick) at a 3.6% concussion rate versus 8.3% for boil-and-bite guards chewed down to 1.34 mm by injury2. Custom devices also stay in the mouth — they're comfortable enough that athletes don't spit them out, which keeps the protection available in the moments it's needed.
Does NeuroGuard+ "prevent" concussions?
No — and that distinction matters. NG+ is engineered around the jaw-stabilization, force-dissipation, and airway mechanisms research associates with lower head acceleration and better-preserved function131. It does not prevent concussions in any individual collision, and no equipment does. It's a research-backed brain-protection appliance and one layer of a multi-layer approach that also includes helmet quality, neck strengthening, rule compliance, and concussion management.
References
- 1. Eliason PH, Galarneau JM, Kolstad AT, et al. Prevention strategies and modifiable risk factors for sport-related concussions and head impacts: a systematic review and meta-analysis. British Journal of Sports Medicine. 2023;57(12):749-761. doi:10.1136/bjsports-2022-106656
- 2. Winters JE Sr, DeMont R. Role of mouthguards in reducing mild traumatic brain injury/concussion incidence in high school football athletes. General Dentistry. 2014 May/Jun;62(3):34-38. Academy of General Dentistry
- 3. Hutchison DD, Madura C, Hutchison MC. Impact of an improved mandibular rest position via custom mouth guard on the incidence of concussions in athletes. (Manuscript; Michigan State University College of Human Medicine; Helen DeVos Children's Hospital; Associates in Family Dentistry.) 2018. Disclosure: corresponding author invented the studied device.
- 4. Singh GD, Maher GJ, Padilla RR. Customized mandibular orthotics in the prevention of concussion/mild traumatic brain injury in football players: a preliminary study. Dental Traumatology. 2009 Oct;25(5):515-521. doi:10.1111/j.1600-9657.2009.00808.x
- 5. Daneshvar DH, Baugh CM, Nowinski CJ, McKee AC, Stern RA, Cantu RC. Helmets and Mouth Guards: The Role of Personal Equipment in Preventing Sport-Related Concussions. Clinics in Sports Medicine. 2011 Jan;30(1):145-163. doi:10.1016/j.csm.2010.09.006
- 6. Garner DP, McDivitt E. Effects of mouthpiece use on airway openings and lactate levels in healthy college males. Compendium of Continuing Education in Dentistry. 2009 Jul-Aug;30 Spec No 2:9-13. PMID: 19774773
- 7. Garner DP, Lamira J. Respiratory outcomes with the use of a lower custom fit genioglossal-effecting oral appliance. Clinical and Experimental Dental Research. 2020;6(1):100-106. doi:10.1002/cre2.254
- 8. Collins CL, Fletcher EN, Fields SK, et al. Neck strength: a protective factor reducing risk for concussion in high school sports. Journal of Primary Prevention. 2014;35(5):309-319. PMID: 24930131
- 9. Knapik JJ, Hoedebecke BL, Mitchener TA, Lee RC. Effectiveness of Mouthguards for the Prevention of Orofacial Injuries and Concussions in Sports: Systematic Review and Meta-Analysis. Sports Medicine. 2019;49(8):1217-1232. doi:10.1007/s40279-019-01121-w
- 10. King D, Hume PA, Brughelli M, Gissane C. Instrumented mouthguard acceleration analyses for head impacts in amateur rugby union players over a season of matches. The American Journal of Sports Medicine. 2015;43(3):614-624. doi:10.1177/0363546514560876
- 11. Tanaka Y, Tsugawa T, Maeda Y. Effect of mouthguards on impact to the craniomandibular complex. Dental Traumatology. 2017;33(1):51-56. doi:10.1111/edt.12283
- 12. Di Virgilio TG, Hunter A, Wilson L, et al. Evidence for acute electrophysiological and cognitive changes following routine soccer heading. EBioMedicine. 2016;13:66-71. doi:10.1016/j.ebiom.2016.10.029
- 13. Pitteu C, Lepère P, Poisson P, et al. A custom-made mouthguard reduces head acceleration during soccer heading and prevents acute electrophysiological and cognitive changes in amateur male players. EBioMedicine. 2025;115. PMID: 40179663
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