European Journal of Prosthodontics and Restorative Dentistry

cover art

Cover Date:
March 2016
Print ISSN:
0965-7452
Electronic ISSN:
2396-8893
Vol:
24
Issue:
1

The Accuracy of Fit of Crowns Made From Wax Patterns Produced Conventionally (Hand Formed) and Via CAD/CAM Technology

The Accuracy of Fit of Crowns Made From Wax Patterns Produced Conventionally (Hand Formed) and Via CAD/CAM Technology

Hawa M. Fathi, Azal H. Al-Masoody, Narjes El-Ghezawi, Anthony Johnson


ABSTRACT
Objective: the aim of this study was to compare the marginal and internal fit accuracy of crowns constructed using three different wax production methods; conventional, milled, and 3D printed and utilizing three different cement gap thicknesses.
Methods: 15 identical stone dies were made for each method. Wax patterns were produced and then cast into metal crowns, which were assessed for differences in accuracy of both marginal and internal fit. Measurement points were 4 points per crown; occlusal, axial, marginal gap, and marginal discrepancy points. A silicone impression technique and conventional cementation technique were employed to facilitate the measurements.
Results: there was no significant difference (p> 0.05) in accuracy between the digitally and manually produced crowns, with the 3D printed crowns being slightly more accurate. Whereas, statistically significant differences were noticed between the conventional versus printed groups, in occlusal and marginal gap points (p< 0.05).
Conclusion: The marginal and internal fit of 3D printed wax patterns is more accurate
than the other two production methods. The milling of wax crowns is as accurate as the conventional hand carved production in terms of internal and marginal fit. The manufacturer recommended offset/die-spacer of 30μm produced the most accurate internal and marginal fits.

Keywords: Marginal Gap, Crowns, Internal Fit, CAD-CAM, Cementation

doi: 10.1922/EJPRD_1444Fathi08

Article Price
£15.00
Institution Article Price
£
Page Start
10
Page End
17
Authors
Hawa M. Fathi, Azal H. Al-Masoody, Narjes El-Ghezawi, Anthony Johnson

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  1. Low Energy Surface Activation of Zirconia Based Restorations
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  3. 9

  1. The Accuracy of Fit of Crowns Made From Wax Patterns Produced Conventionally (Hand Formed) and Via CAD/CAM Technology
  2. 10
  3. 17

  1. Impact of Referral Protocols on the Dental Management of Patients Undergoing treatment for Head and Neck Oncology in Northern Ireland
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  1. Zirconia Abutment Supporting All Ceramic Crowns in the Esthetic Zone: Interim Results of a Prospective Study
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  1. Prosthetic Complications and Maintenance Requirements in Locator-attached Implant Supported Overdentures: A Retrospective Study
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  1. Prosthodontic Rehabilitation for a Patient with Ellis-Van Creveld Syndrome: A Case Report
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  1. Implant Treatment in Patients with Sjogren’s Syndrome: A Review of the Literature and Two Clinical Case Reports
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