A cavity caught early is treated with a filling. If it reaches the pulp, the living part of the tooth, a root canal treatment is needed: the inside of the tooth is cleaned and sealed, so the tooth stays in place.
For many of these treatments we use a rubber dam, the coloured sheet placed around the tooth. It keeps the tooth away from saliva and germs and protects you from the materials, so they can't be swallowed or breathed in.
Our practice's dentists take care of this.

It depends on what you need, and you know before we start: after the visit you get a written estimate, item by item. If there's more than one option, you get them all, each with its cost.