What does the science say?
The effectiveness of oral appliances has been demonstrated in multiple clinical trials. In one trial, 42 patients suffering from sleep apnea were enrolled, and out of them, 38 completed the study. The mean age of the participants was 46. At the end, almost half of the patients benefited from oral devices against 18.4% in the placebo group. This study clearly demonstrated the effectiveness of these devices. Even though efficacy is not very high, it's important to keep in mind that it is one of the most comfortable and safer of the treatment options.