G.B.
My husband did this through the dental college at OU Health Science Center here in OKC. They made a mold of his mouth with that dental goo, it goes everywhere too....
The appliance was so painful for hubby. It basically pulls the lower jaw forward to place the tongue in a position where he can't snore. The jaw joint becomes painful and inflamed over time. Hubby got to where he wouldn't even speak because just moving to say something nearly made him cry. Try sitting with your mouth like that for a while, your lower jaw poking out and the top one normal. It gets tired of it.
The best day was when he got his C-PAP. The first one didn't work out so well, that doc didn't listen well and turned it up so much that hubby's stomach was bloated out from all the air blowing in.
The next doc listened and helped hubby pick the right face gear and he sleeps with it every night and is doing so much better.