I'm returning this dental guard. I had been using it at night for only about a week when I noticed my front top teeth were pointing inwards towards my mouth! I couldn't close my jaw properly. It was disturbing. Luckily a few nights of not using it seems to have let my mouth readjust to its usual self. Even aside from the terrifying insight that my teeth were wandering, I found the edges of the guard too high. They rubbed too much into my cheeks and were causing problems with the skin there.