I have a similar problem, I created a vampire and put double fangs on his human version, but when I use the cheat to change career clothes in the detective career, they disappear even on other clothes that are not work clothes! When I create a vampire sim without teeth, put him in the world and go to change sim (in any edit option, in the mirror, through the cheat or in manage world) and put the double fangs, they do not save! The teeth return to being human, you practically have to create a sim in a new game from scratch, and change the career clothes manually as a separate look.
Teeth bug
