Do Oral Mouthguards Affect Ventilation?

Abstract

Athletes participating in contact sports wear mouthguards (MG) to decrease the risk of concussions and orofacial injuries. However, many athletes resist wearing mouthguards citing reasons that include discomfort, problems with speech and breathing during play. Breathing difficulties may suggest some limitations with ventilation. PURPOSE To examine peak inspiratory and peak expiratory air flow at specific ventilatory rates using different types of MG and a no MG condition. METHODS Seven MG (3 stock, 3 boil and bite, and 1 custom-fitted; 5 unimolar and 2 bimolar) and a no MG condition were compared. MG were fitted into an oral dental model and air was ventilated through the model at three flow rates (30, 45, 60 strokes·min−1) using 2 and 3 liter syringes. Inspiratory and expiratory flows were recorded using a Medisoft Ergocard. Peak flow (L·s−1), FEF25, FEF50, FEF75, FIF25, FIF50 and FIF75 were recorded for 10 strokes at each ventilation rate. Data were analyzed using a 3-way (8 MG; 6 flow rates; 2 flow directions Insp/Exp) repeated measures ANOVA for the dependant variable, peak flow. RESULTS There was a significant main effect for MG (F = 11.97; p < 0.001) with lower peak air flow for the two bimolar MG compared to the no MG condition. There were significant interaction effects between MG and flow rates. At the lowest ventilation (60 L·min−1), peak flow was similar to the no MG condition for 5 of the 7 MG. At the highest ventilation (180 L·min−1), peak flow was significantly higher with no MG compared to 4 of the 7 MG conditions, including both bimolar MG. CONCLUSIONS These findings suggest that mouthguards do not impair ventilation at low flow rates, however peak flow is lowered at high ventilation with bimolar mouthguards and some unimolar mouthguards.