Absolutely, you can wear a mouthguard with a CPAP! In fact, most sleep physicians recommend using the two jointly before giving up on your CPAP altogether. However, if you’re someone who is CPAP intolerant and looking for an alternative sleep apnea treatment, then an oral appliance could be the solution that you’re looking for.
Since a CPAP physically forces air into your lungs, it doesn’t matter if you’re wearing a sleep mouthguard. In fact, an oral appliance might actually help your CPAP to work better because there aren’t physical tissues interfering with your airflow. It’s the oral appliance’s job to keep your lower jaw slightly forward, preventing blockage at the back of your throat. If you were to wear the mouthguard without a CPAP, you would be breathing naturally as opposed to having positive air pressure physically pushing the oxygen into your body.
Many people find that if they can’t sleep with a CPAP machine (due to their size and noise) they’re able to switch to a dental appliance instead. But never stop using your CPAP without first consulting with your physician and sleep dentist.