I've been using the Somnodent MAS since November 2008 and it is amazing at the difference it makes. I'll make a suggestion based solely on my experience. Adjustment of the MAS is made in 1/10 millimeter increments, so 10 "adjustments" equals 1 millimeter of movement (you might know that already). I read all the stuff about why the dentist should do this and why a PSG should be done periodically during this adjustment period. having discussed it with my dentist who also uses the device we decided I'd just do the adjustments myself. Sleep studies are a pain, I hardly ever sleep and honestly, beyond the potential for over adjustment of the lower jaw could see no reason to follow some strict protocol. My guess is it will be different for different people, the biggest concern is like I said, over adjusting to the point of pain in the jaw. My device started at 3mm and I have adjusted out to 5.5mm, that took me a couple of weeks and I did based on how I feel the next day. human vs. not human. I have gone to 5.8mm but didn't feel as good as I did at 5.5mm. This is the reason I went in for another PSG to get a bearing on how this is helping, I felt I'd hit a plateu in adjustments I could readily tell.
All that said, two things:
First, if you're having teeth pain while wearing the device or continued pain after taking it out (say beyond an hour) then the mold most likely isn't quite right and it should be something the dentist can fix in the office. Otherwise it may be normal, I got crooked teeth and he told me it would probably move them initially, much like an Invisiline would do albeit only minorly but still enough to cause some initial discomfort that should go away.
Second if you chose to make your own adjustment the biggest concern is the jaw pain. If you have jaw pain while wearing it or pain that doesn't fade away in a half hour or so or your jaw begins to click, pop or stick, the adjustment is too much, just back it off. I made adjustments in 3mm turns the first week, at about 4.8 or so I could tell significant difference in how I felt and morning discomfort so I slowed it down. Listen to your body it'll tell you whether your going too fast or not. Just be aware of how you feel, there will come a point where you won't be able to tell if it's doing anything and that's when you need to probably has a PSG to get an idea where it's at.