I have a bad jaw, in that the right-hand joint ain’t quite right. Lately it’s been hurting like mad, and so I bought a mouthguard to keep my teeth apart. Thus, even if I’m clenching my teeth, I still have a good separation.
The problem, apart from the root problem of the bad jaw, is that the mouthguard keeps making me gag. I don’t know why. It’s annoying. It’s like a bonified gag reflex every now and again.
I just thought I’d share.
My girlfriend grinds her teeth at night. She tried getting a mouthguard, but it was problematic - it didn’t make her gag, but she’d drool all over everything and it would come out somehow while she was sleeping. Her dentist made her a tiny little plastic piece that clips on her two top front teeth. It’s barely noticeable to me, and she got used to it really quickly as well. It was expensive, but her insurance covered part of it.
I don’t know if something like that would work with jaw problems, especialy if they’re focused on one side. But it might be worth looking into.
Before you zip off to the dentist to get an expensive mouthguard that won’t make you gag, you can try the low-tech solution:
(1) Take the mouthguard and cut about 1/3 of an inch off the very back (where it sits on your back teeth). It won’t wrap around your back teeth anymore (making it more likely to fall out) but it will still prevent you from grinding. Moreover, if you cut it far enough up, it won’t be touching the back sides of your tongue, which IME is what stimulates the gag reflex.
(2) If it doesn’t work, cut it up a little further, and see if you can stop the mouthguard from triggering your gag reflex.
(3) If that doesn’t work, you’re out 20 bucks plus the 1000s of bucks for the dentist.
Good luck!
The Doctor
I have a mouthguard…er, or rather a “night appliance” for my TMJ. It’s blue with a bit smiley face on the bottom, and it glows in the dark!
I suspect mine is different than yours, though. It sits in the front of my upper pallate and just has some metal pointy things that go around my teeth. The front is a big lump and it basically keeps my lower jaw from sliding backwards while I sleep.
I love my night appliance. It’s like a pacifier - I can’t sleep without it anymore 
That feels much better.
I don’t know which one you are using, but there are mouth guards that are only for your upper row of teeth. You put them in boiling water for 30 seconds, then quickly dip in cold water, stick on your upper teeth and SUCK HARD. This forms the whole thing to your teeth and it sorta clips in and out. I find them much more comfortable than other mouth guards, and you can trim them, adjust them, whatever.
-Tcat
Hear, hear! That’s the kind I use, on my dentist’s recommendation, and it’s so comfortable I don’t even notice it. It’s easy to trim off a bit of the ends, too, if you need to.