My husband suffered trying to get relief with the C-pap and the numerous masks that he was told to "keep trying another mask". It was awful. Dr. Core to the rescue! He has a kind and gentle manner and his staff is kind and efficient. Thank You, Dr. Core for a good night's sleep ~ for both of us. Keep up the great work to eliminate sleep apnea. Why would anyone ever use an annoying, cumbersome, noisy C-pap machine is beyond me when Dr. Core can and has helped my husband's sleep apnea with a simple dental device.