Accuracy of a new concept for image-guided dental implantology

Abstract

The accuracy of a novel image-guided template production (IGTP) technique was tested in three phantom studies. Class III dental stone casts were prepared with integrated lead pellets and scanned in a spiral-CT wearing a modified Vogele–Bale–Hohner (VBH) mouthpiece (Medical Intelligence, Germany) with an external registration frame. Using the optical based Treon navigation system (Medtronic, USA) the dental casts were registered to the CT data and a surgical path to the target pellets was planned. In study 1, drillings were performed using the aiming device of the navigation system. In studies 2 and 3, the drillings were performed using templates made by an indirect and a direct burr tube positioning method. The evaluation was done on the postoperative CT data. Precise drillings with submillimetric mean accuracy and a maximum deviation of 1.2 mm could be achieved with both methods. Considering the accuracy (0.5 vs. 0.6 mm) and workflow, the direct method is superior to the indirect method. The results are well comparable to published accuracy analyses of burr tracking. For patient application, a safety distance of 1.5 mm is necessary to reliably avoid damaging critical anatomical structures.