There are several kinds of “fillings” or restorations (as we like to call them) used in dentistry. They can be “silver fillings”-Amalgam, “white fillings”-Composite, porcelain (crowns or cerecs), Gold or a temporary material. Each of these have their own pros and cons.
Usually after a root canal treatment is completed, a protective restoration is placed over your tooth. This restoration generally placed immediately, must be periodically monitored by your general dentist. A root canal treated tooth becomes weaker over time. Moreover, an added protection in the form of a Crown or “Cap” could be required which is done by your general dentist.
However, a 6-12 months observation period is suggested before you invest in a crown, to see whether the root canal treatment has succeeded or not.