en
Scientific article
English

Fractographic analyses of three ceramic whole crown restoration failures

Published inDental Materials, vol. 21, no. 10, p. 920-929
Publication date2005
Abstract

Summary Objectives: Develop fractographic techniques to perform failure analyses of three ceramic whole-crown clinical failures. Methods: Three clinical whole-crown failures of different ceramic material systems were studied. The systems included appropriate veneers applied to core materials of cold isostatically pressed alumina, injection molded alumina/alumina–magnesia spinel, and hot pressed lithium disilicate. The surface topography was examined for classical fractographic features, utilizing both optical and scanning electron microscopes independently as well as group examination by four fractographers. Results: All three restorations displayed many common fractographic features, the most important of which was wake hackle. Wake hackle occurs when an approaching crack frontsweeps by a small bubble or discontinuity in a brittlematerial, leaving a trail. The resulting trails can be used to trace back crack progression to an initial starting area. Wake hackle was found to be common in the veneer portions of the crowns, and the strategy of creating a wake hackle map enabled crack paths to be traced from a core area outward in all three restorations. The fracture origin areas were located where hoop stresses are high. Another helpful fracture feature was compression curl, an indication of flexural stress, most visible under low incident optical lighting. Significance: This study indicates that fractographic analyses can be productively performed on ceramic whole-crown failures. Optical examination under low incident lighting and wake hackle mapping were developed as promising techniques. Hoop stress was implicated as a concern in the three studied specimens, and should be considered when analyzing other whole-crown failures.

Keywords
  • Fractography
  • Failure analysis
  • Whole crown fracture
  • Wake hackle
  • Crack path
Citation (ISO format)
QUINN, J et al. Fractographic analyses of three ceramic whole crown restoration failures. In: Dental Materials, 2005, vol. 21, n° 10, p. 920–929. doi: 10.1016/j.dental.2005.01.006
Main files (1)
Article (Published version)
accessLevelRestricted
Identifiers
ISSN of the journal0109-5641
375views
1downloads

Technical informations

Creation10/18/2017 12:36:00 PM
First validation10/18/2017 12:36:00 PM
Update time03/15/2023 2:29:34 AM
Status update03/15/2023 2:29:34 AM
Last indexation01/17/2024 1:36:19 AM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack