Always find an experienced mercury-free dentist to place indirect composites. Indirect composites are just as expensive as gold. When an initial amalgam filling is placed in a tooth that has never had one before, a larger amount of the tooth has to be drilled away. If a small composite is placed for just a few more dollars, less of the tooth must be drilled away. This larger amount of drilling weakens the tooth hastening the day when tooth will need an expensive crown, root canal or when it must be pulled.
Small composites are only a few dollars more expensive than amalgam and last just as long.
At the very least, once a large amalgam filling has been placed, it must be replaced either with another amalgam or with a much more expensive indirect composite or gold inlay. It can be replaced with regular composites, but large composites are weaker and don't last more than five or six years. Conclusion Cleaning of old cavitations from where teeth were previously extracted is reasonably inexpensive and may produce dramatic results. Extraction of a root canal filled tooth can be more expensive since it will require replacement with some kind of bridge, but can also lead to great improvement sometimes. It sometimes leads to dramatic improvement, but usually does not.