3D Registration Accuracy of a Novel Marker-Free Technique for Double-Scan Protocol.

Purpose: The aim of this retrospective study was to introduce a novel technique of a double-scan protocol with markerfree registration and compare it to the already-used techniques regarding the accuracy of registration.

Materials And Methods: Fifty-nine fully edentulous patients underwent double-scan procedures by three different methods: the barium sulfate method for 11 patients; the gutta-percha method for 26 patients; and the marker-free method for 22 patients. Point-to-point registration of the two scans was followed by a voxel-based surface "best fit" registration.