I have been using this product for a few years now. While it is the best dental appliance I have found, there are a few peculiarities. While it is made out of very good material, there is something about how it seems to adhere to your back teeth that causes undo downward pressure on them. I actually had to end up having a root canal. I can’t say it was the appliance for sure, but it was likely. Now I cut that material down significantly to minimize downward pressure. A thoughtful redesign of some sort might be in order. All that being said, I don’t want to have to resort to the dreaded CPAP so I’ll keep using this.