Should one be worn? I know we don't fall on our faces too much, but at 30 km/h it could do some brutal dmg to your face.

Or you could get a full face helmet.

This is a common misconception; mouthguards are not there to protect your teeth. They are there to keep you from getting a concussion. Often times when you bash or knock your head your jaw will snap shut, quite forcefully at that. The shockwave or whathaveyou is strong enough to hurt the jelly inside your nut. It has been my personal experience that the mouthguard will actually do more damage to your teeth than not using them in a jaw-snap-shut situation, but i'd rather jack my teeth than my brain.

In conclusion, yes, you *should* wear one. No, i must admit, i don't.

I am with ubie...good idea, but I doubt I will wear one.

Count me in with the good idea crowd.

Im still going with fullface helmets...

Doesn't do diddly to prevent the concussion that the mouth guards prevent. A mouthguard can prevent serious injuries such as concussions, cerebral hemorrhages, incidents of unconsciousness, jaw fractures and neck injuries by helping to avoid situations where the lower jaw gets jammed into the upper jaw. Mouthguards are effective in moving soft issue in the oral cavity away from the teeth, preventing laceration and bruising of the lips and cheeks, especially for those who wear orthodontic appliances.
I've seen friends of mine get a concussion while wearing full faced hockey helmets (while playing hockey) these were the same people who spat out their mouthpiece as soon as the were out of the coach's sight.

Here's my 2¢ for whoever cares to read ....

When I 1st started riding Mtn. Bikes, I was concerned about a mouth piece. Since then, and after about 36,000 miles later, I have come to realize that those teeth guards may not be a necessity afterall. I may fall this coming Friday & bust all my teeth out, but I'd bet against it !!!!

PS: I've rode as fast as 46 mph, and as slow as 0 mph ( while falling off the bike of course ).

Wouldn't it make it harder to breath when going all out? When I'm tired and going up hills, I usually breath through my mouth. I can see it being a good idea for brief time intervals, like putting one in right before hitting a jump or something, but not for all around use. I'd never do it.

I really thought getting knocked out was as much as riding as flat tires or atleast seems that way in ohio.

chewing gum is an issue for me....a mouthguard would DEFINITELY BE.