APAP to measure MAD effectiveness/titration

I have a Tap 3 oral appliance, and am using my Resmed S9 APAP at minimum pressure (4.0) to get a rough idea of how effective the Tap 3 is, and which titration setting is best.

I know this is a relatively crude compared to a proper overnight sleep test, but my insurance won't pay for that at this point. Hopefully in the near future I will have an overnight test with the Tap 3, but in the meantime I'm trying to get approximate information.

1) I'm getting an AHI average of a bit over 3.0, with APAP at min/4.0 pressure, with Tap 3 at specific setting. Is there a way to approximate what my AHI would be with Tap 3 but no APAP (ie, without 4.0 pressure)? I have no way of measuring AHI without APAP, and can't set lower than 4.0. (My APAP settings before Tap 3 were min: 7, max: 14. Pressure of 8 recommended after sleep study, for CPAP use, not MAD).

2) Is there a home test that might be more helpful?

I do have an oximeter, and use Oscar software to view data from that and APAP.

My suggestion would be to run the APAP in Auto mode for a few nights with the Tap 3 device in, and then do it again with the Tap 3 out. Then observe the average median pressure in OSCAR under each mode of Tap in and out. This should be displayed in the statistics page. That should give you an estimate as to how much the Tap 3 device is reducing AHI. The higher the difference the more effective it is. With what you have done so far it would seem like the Tap 3 alone is giving you an AHI greater than 3.

Thanks Sierra, I'll give that a try. Would you suggest I use the min/max settings that seemed to work best without the appliance?

"With what you have done so far it would seem like the Tap 3 alone is giving you an AHI greater than 3." Right, but that's with pressure at 4--does that amount of pressure provide therapeutic value?