Having a supernumerary tooth show up on a patients tooth chart would be useful because as like when a patient has some baby teeth and some adult teeth its better for the patient and the doctor to be able to quickly look at a patients chart and be able to tell all the patients mouth conditions without having to search around the chart for all the conditions. You should add a button to the "conditions" tab as a supernumerary tooth
Yes! And show an icon instead of requiring that the tooth be drawn. Children's charts tend to end up looking messy.