Are Nasal-Exclusive Masks (like the n30i) Good for Mouth Breathers?

I’ve tried different masks as a new CPAP user, and so far the n30i is proving the most comfortable to use, and my sleep reports have been all green with no issues.

The only problem is that for someone who potentially opens his mouth when sleeping (I don’t have a partner to verify, but the evidence is there, like my dentist remarking on my swollen tongue as well as waking up with a dry/scratchy throat), I’m wondering if it’s necessary for me to find a way to cover my mouth, either by using a mask that covers both nose and mouth or getting a sleeping strap. The latter would have to be something really comfortable as I’m already wearing enough crap on my face (the CPAP mask plus a sleeping mask for my eyes). I’m also looking to try the F40 as one final alternative before I change masks this weekend.

Advice is welcome.