I ended up using the Millennium Teeth from DAZ, which has a nice pointy option.  I used the Stephanie Set (there are a few sets of teeth, all from DAZ1 folk, I think), which seemed a good match for Olivia/Ahava.  Didn't even have to resize them, as it turned out.

A bit tricky placing them in the head, but I had a pose with a slightly open mouth to start.  Then put the teeth in the scene at about the right spot (over Umira's head) using the side view camera.  Then I simply moved them down until I could see them through the open lips, using both the side and front views of the head to adjust them up and down & forward and back, until I got them when I liked them

Then I parented the teeth to the head.

Then I went to the Materials Room and made the material on the original teeth 100% transparent.  Maybe there was a better way to "pull" the original teeth, but that's what I came up with.

The new teeth have their own open & close morph.  So when I open the character's mouth, I have to then go to the teeth figure and open them, too, an appropriate amount.  Again, maybe there's some easier way to do that, but I don't know it.

All in all, it seems to work pretty well, and it achieves the effect I wanted.  (Tip for Writers: One should always be careful when describing a character that one will one day have to illustrate.)  We'll see how it turns out in the final render(s).

Thank you, one and all, for all your great suggestions!

I will put up some pictures of the final results when I'm on the rendering computer later (it's busy rendering now).

 Stephen D. Sullivan

www.stephendsullivan.com

Adventure guaranteed.  (Monsters optional.)