Tooth morphology fusion technique is more accurate than conventional technique in transferring morphology of provisional to definitive screw-retained, implant-supported crown: A preliminary intervention study.

PURPOSE: To compare the accuracy of the tooth morphology fusion (TMF) digital technique and customized impression transfer coping (conventional) technique when transferring the morphology of a provisional crown to a definitive screw-retained implant-supported crown. METHODS: Six cases of partial edentulism (one anterior and five posterior) treated with oral implant placement in our clinic for the loss of three or fewer teeth in the maxilla or mandible between April 2017 and September 2018 were included. After implant placement and re-entry surgery, provisional restorations were made and adjusted to obtain the ideal morphology. Two definitive restorations were constructed by transferring the complete morphology of the provisional restorations, including the subgingival contour, using the TMF digital and conventional techniques. Three sets of surface morphological data were obtained using a desktop scanner. The three-dimensional total discrepancy volume (TDV) between the provisional restoration (reference) and the two definitive restorations was digitally measured by overlapping the surface data of the stone cast using the Boolean operation. Each TDV ratio (%) was calculated by dividing the TDV by the volume of provisional restoration. The median TDV ratios for TMF and conventional techniques were compared using the Wilcoxon signed-rank test. RESULTS: The median TDV ratio between provisional and definitive restorations constructed using the TMF digital technique (8.05%) was significantly lower than that obtained using the conventional technique (13.56%, P < 0.05). CONCLUSIONS: In this preliminary intervention study, the TMF digital technique was more accurate than the conventional technique for the transfer of morphology from provisional to definitive prosthesis.

Fixed Partial Denture Designed by Combining the Whole 3D Digital Surface Morphology of the Provisional Restoration and Abutment Teeth Surfaces.

We introduce a new digital workflow to fabricate a fixed partial denture (FPD) utilizing the three-dimensional surface morphology of provisional restoration (PR) and abutment teeth. Scanned images of the full maxilla with abutment teeth, full maxilla with PR, and PR alone were superimposed. The surfaces of the final FPD were designed based on the entire morphology of the PR and abutment teeth surfaces. The inner and outer surfaces converged at the margin lines of the abutment teeth. Fine modifications to the final FPD design were performed manually, and the final FPD was fabricated and successfully installed in the patient.

In silico comparison of the reproducibility of full-arch implant provisional restorations to final restoration between a 3D Scan/CAD/CAM technique and the conventional method.

PURPOSE: The aim of this article was to investigate the accuracy in the reproducibility of full-arch implant provisional restorations to final restorations between a 3D Scan/CAD/CAM technique and the conventional method. METHODS: We fabricated two final restorations for rehabilitation of maxillary and mandibular complete edentulous area and performed a computer-based comparative analysis of the accuracy in the reproducibility of the provisional restoration to final restoration between a 3D scanning and CAD/CAM (Scan/CAD/CAM) technique and the conventional silicone-mold transfer technique. Final restorations fabricated either by the conventional or Scan/CAD/CAM method were successfully installed in the patient. The total concave/convex volume discrepancy observed with the Scan/CAD/CAM technique was 503.50mm(3) and 338.15 mm(3) for maxillary and mandibular implant-supported prostheses (ISPs), respectively. On the other hand, total concave/convex volume discrepancy observed with the conventional method was markedly high (1106.84 mm(3) and 771.23 mm(3) for maxillary and mandibular ISPs, respectively). CONCLUSIONS: The results of the present report suggest that Scan/CAD/CAM method enables a more precise and accurate transfer of provisional restorations to final restorations compared to the conventional method.