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More than likely your CPAP is set at 11 cm. Given that your CPAP is quite old, I would recomend you get your CPAP checked to ensure that you are getting the proper pressure. The company you purchased your CPAP from should have a copy of your prescription and should also help you with the pressure check.
Comfort is very important when wearing a CPAP mask. Some CPAP users find a full face mask is more comfortable, but a full face mask is sometimes more difficult to get use to and also you may experience problems with leaks. Often full face mask will make the bridge of your nose sore even with the best fit. If you are waking up with really dry mouth your mouth may still be opening even with the chin strap. If you are making snoring like noises, you may be breathing through your mouth some. If so you may want to consider a full face mask
After 5 years, it is a good time to reevaluate the effectiveness of your CPAP therapy. Has your weight changed significiantly since your last sleep study? Are you feeling more tired or less rested? Are you snoring again?
We will be happy to help you with a new mask and supplies. If you are looking for a gel type mask, Respironics makes a full face comfort gel and also a nasal gel mask, the comfort gel. On our website you will also find sizing guides to help you choose the correct size.
Please contact us again when you have made your choice.
Debbie Shirley,RRT