Mouthguards vary in comfort, fit and protection
Pressure-formed, custom-made mouthguards are the best
Proform is the best material available
Mouthguards should be replaced every 1-2 years
Stock mouthguards are made of rubber or polyvinyl. While the physical and mechanical properties of these mouthguards are acceptable, sizes are limited often resulting in a loose and cumbersome fit. They also may interfere with breathing and speech, and require that the jaws be closed to hold the mouthguard in place.
Since little can be done to adjust the fit of these mouthguards, many athletes find them uncomfortable and consider them the least satisfactory of all the types available.