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Computer-aided preoperative planning and surgical templates in implant dentistry for the cases involving metal artifacts

In the field of implant dentistry, there is a trend towards computer-aided preoperative planning and CT-derived surgical templates. However, for the cases involving patients with metallic crowns or fixed partial dentures, streak artifacts in the original computed tomography (CT) images are a major problem, which often inevitably affects the design and manufacturing the surgical templates. In this study, a modular preoperative planning software was developed for computer-aided oral implantology and the following registration procedure was realized using both surface and volume rendering technique. By superimposing the 3D laser-scanned dentition surface model to the volume rendering image from CT data, an “augmented” skull model with detailed dentition information was obtained. On the basis of this fusion data and preoperative planning information, the surgical template was designed and finally fabricated via stereolithography technique. A clinical report for a partially edentulous patient with metallic crowns demonstrates the feasibility, reliability and validity of this technology.