I'm trying to edit this COM female head so that the teeth don't show when the mouth is closed.
When mouth is closed, white teeth are visible. http://imageshack.us/a/img145/2225/screenshot4pl.jpg
When mouth is open, white teeth are visible, which is how it should look. http://imageshack.us/a/img233/8092/screenshot2kg.jpg

After adjusting the UV where the teeth are in NifSkope, I managed to move the mapping to where the lips are instead of where the teeth are.
Now when mouth is closed, the teeth don't show through the lips http://imageshack.us/a/img69/7804/screenshot6ad.jpg
But when mouth is open, teeth are same color as lips so it looks like she has no teeth. http://imageshack.us/a/img33/8206/screenshot10ab.jpg

I'm thinking the problem is the lips not closing all the way. I was trying to sculpt them in Blender but I couldn't get any of the sculpt tools to work at all. Is it supposed to be highlighted? http://img22.imageshack.us/img22/6735/blenderh.jpg
Would someone help me with this? Thanks.

I uploaded the file http://www.4shared.com/rar/NgMRXIX9/COM_HEAD_Data_Files.html in case somebody wants to take a look at it; one NIF and one DDS.