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Efficiency of a mathematical model in generating CAD/CAM-partial crowns with natural tooth morphology

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Abstract

The “biogeneric tooth model” can be used for computer-aided design (CAD) of the occlusal surface of dental restorations. From digital 3D-data, it automatically retrieves a morphology matching the natural surface left after preparation. This study evaluates the potential of this method for generating well-matched and well-adjusted CAD/computer-aided manufacturing (CAM) fabricated partial crowns. Twelve models with partial crown preparations were mounted into an articulator. Partial crowns were designed with the Cerec 3D CAD software based on the biogeneric tooth model (Biog.CAD) and, for control, with a conventional data-based Cerec 3D CAD software (Conv.CAD). The design time was measured, and the naturalness of the morphology was visually assessed. The restorations were milled, cemented on the models, and the vertical discrepancy and the time for final occlusal adjustment were measured. The Biog.CAD software offered a significantly higher naturalness (up to 225 to 11 scores) and was significantly faster by 251 (±78) s in designing partial crowns (p < 0.01) compared to Conv.CAD software. Vertical discrepancy, 0.52 (±0.28) mm for Conv.CAD and 0.46 (±0.19) mm for Biog.CAD, and occlusal adjustment time, 118 (±132) s for Conv.CAD and 102 (±77) s for Biog.CAD, did not differ significantly. In conclusion, the biogeneric tooth model is able to generate occlusal morphology of partial crowns in a fully automated process with higher naturalness compared to conventional interactive CAD software.

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The authors declare that they have no conflict of interest.

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Authors and Affiliations

  1. Division of Computer Restorations, Department of Preventive Dentistry, Cariology, and Periodontology, Center for Dental and Oral Medicine, University of Zürich, Plattenstrasse 11, 8032, Zürich, Switzerland

    Andreas Ender, Werner H. Mörmann & Albert Mehl

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  1. Andreas Ender
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  2. Werner H. Mörmann
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  3. Albert Mehl
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Correspondence to Andreas Ender.

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Ender, A., Mörmann, W.H. & Mehl, A. Efficiency of a mathematical model in generating CAD/CAM-partial crowns with natural tooth morphology. Clin Oral Invest 15, 283–289 (2011). https://doi.org/10.1007/s00784-010-0384-z

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  • DOI: https://doi.org/10.1007/s00784-010-0384-z

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