I have started to add tones and details to the face. I don't find many paintings, where the teeth are showing, that I feel are successful, so it is with trepidation that I approached this pose. I have tries not to make them too prominent. One of the biggest problems with teeth in paintings and drawings, in my view,  is that the spaces between the teeth are over worked and become too dominant.
I shall work more detail and contrast into the eyes in my next session an, perhaps start the build up of hair detail.