How it's done :

During the first visit, decay or fillings are removed. An impression is taken to record the shape of the tooth being repaired. The impression is sent to a dental laboratory that will make the indirect filling. A temporary filling is placed to protect the tooth while your restoration is being made. During the second visit, the temporary filling is removed, and the dentist will check the fit of the indirect restoration. Provided the fit is acceptable, it will be permanently cemented or bonded into place.