A system and method of automated formation of a preparation stub, based on an a priori created computational geometrical model, configured to conform to a prefabricated fixed dental prosthesis, is described. The system includes a digital imaging facility with an image acquiring device and a three-dimensional data digitizer, a modeling facility with an exterior surface design module and an interior surface design module, a fabrication facility operatively with a computer-aided manufacturing module, as well as an application facility including an ablation tool and in-situ preparation module; application facility preferably includes an intra-oral feedbacking appliance with a distance measurement probe for automated feedback-controlled formation of a preparation stub.