Events per Hour Increased with New Mask

I'm a newbie to this forum as well as CPAP therapy so I'd like to throw out a big hello to everyone.

I started with a nasal mask but it was leaking between 25-30 L per minute but my events per hour ranged from 1.1 to 4.9 events per hour, all but 3 whre under 4 for a 10 day period. It didn't make any difference if I used a chin strap or not. My sleep study did show that I had a tendency to sleep with my mouth open especially when on my back.

So, I just got a small full face mask figuring it might help with the leaks especially if they occurred through my mouth. I've only used it the last three nights but the interesting thing that occurred is that the leaks dropped down to 9.6-10.8 L per minute while my events increased, ranging from 10.2-12.2 per hour. I changed the mask being used on my CPAP machine from nasal to full face thinking it would compensate for any pressure change that might be required. Is that it is suppose to do? If so, I don't think pressure could be the culprit, or could it?

Any thoughts or assistance would be appreciated.

Thank you --Howard

A little more info would help I guess. What machine and what pressure setting? What mask(s)? If the mask isn't leaking, positive air pressure should be keeping the airway open and lessen obstructive apnea events. Something isn't adding up. If it remains a quandry, go back to the old mask and device a method that works for you for keeping the jaw from sagging and thus, your mouth closed at night. I use a mouth guard and others use straps or tape their mouth shut (not keep for the latter method).