My dentist had another patient who benefited and liked this product— so I had very high hopes. After 2 weeks of using it, I gave up. It is too bulky in the front so my lips would not meet. I could hold them closed while I was awake but hey separated as soon as I relaxed. I ended up mouth-breathing most of the night. I tried using tape to hold them together but the corners separated. My jaw was closed, so a chin strap would not solve the problem. After 2 weeks of excessive dry mouth I gave up. Also, instructions say to trim extra plastic with a sharp scissors. My sharpest scissors did not make a dent. I had to use a razor blade very carefully and it took a long time.