Computer Aided Diagnosis and Design of Implant Abutments

Purpose: Minimal invasive implant therapy has recently gained a growing interest as a standard prosthodontic treatment, providing complete restoration of the occlusal function. A new treatment method (CADDIMA) is recently developed which combines both CTand optical laser-scandata for planning and design of surgical guides, implant abutments and prosthetic devices. In this article the new procedure for minimal invasive implant prosthodontics is described, explained and evaluated for a single clinical case with regard to reproducibility of the drill hole angulation using geometric matching of cone beam Head-CT and optical imaging data. Methods: A “NewTom 3G” cone beam CT-scanner (QR s.r.l., Verona, Italy) and a modified lasertriangulation scanner “D200c” (3Shape A/S, Copenhagen Denmark) were used for imaging. An impression with 3 markers was placed in the patient during CT-scanning and on the gypsum model during optical scanning, so that the surface of mucosal tissue with remaining dentition and antagonists could be observed in a combined 3Dview with the bone structure in the region of interest by the operator using “Cyrtina ® CAD” software (Oratio B.V., Hoorn The Netherlands). Surgical guides (N=5) were designed and produced for both the pilot and the final drill. Results: The positioning of the implant in a virtual cross-sectional view with mucosa and antagonists resulted in an snap-fitting drillguide supported by mucosa and dentition and eliminates the traditional flap surgery by limiting the intrusion size to the diameter of the implant. The difference between the planned and placed implant abutment orientation was within 4.3 o (± 2.96 o (N=5)). Conclusion: The new approach gives the operator full control over the design of the implant prosthondontics for planning of proper occlusal relations and shows promise for further evaluation.. This study was financially supported by a grant TSIT2020 from SenterNovem, The Hague,