I have been using a PureSleep Anti-Snoring Dental Device for more than 2 years. They eliminate my snoring and allow more restful sleep for both myself and my partner. The mouthpiece comes with easy instructions on how to heat and mould it to your teeth. For me, I've found that slight wiggling of it during the moulding makes it less tight and my jaw/teeth don't get sore. It did take awhile to get used to sleeping with it. My lips do not close over it when I sleep. At first I would get a dry tongue/lips, but that doesn't happen any more. I'm not sure how it changed, but it did. I'm now on my 5th set and plan to continue to use PureSleep.