Fracture resistance and failure patterns of endodontically treated mandibular molars with and without glass fiber post in combination with a zirconia–ceramic crown

Salameh, Ziad; Ounsi, Hani F.; Aboushelib, Moustafa N.; Sadig, Walid; Ferrari, Marco

doi:10.1016/j.jdent.2008.03.014

« Previous Next »Journal of Dentistry
Volume 36, Issue 7 , Pages 513-519, July 2008

Fracture resistance and failure patterns of endodontically treated mandibular molars with and without glass fiber post in combination with a zirconia–ceramic crown

Ziad Salameh
- Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
- Department of Research, School of Dentistry, Lebanese University, Beirut, Lebanon
- Department of Dental Materials, School of Dental Medicine, University of Siena, Italy
Hani F. Ounsi
- Department of Research, School of Dentistry, Lebanese University, Beirut, Lebanon
- Department of Dental Materials, School of Dental Medicine, University of Siena, Italy
Moustafa N. Aboushelib
- Department of Dental Material Science, Academisch Centrum Tandheelkunde Amsterdam, Universiteit van Amsterdam and Vrije Universiteit, The Netherlands
Walid Sadig
- Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
Marco Ferrari
- Department of Dental Materials and Restorative Dentistry, University of Siena, Siena, Italy
- Corresponding author at: Dipartimento di Scienze Odontostomatologiche, Università degli Studi di Siena, Policlinico Le Scotte, Viale Bracci 53100, Siena, Italy. Tel.: +39 0577 233131; fax: +39 0577 233117.

Received 30 December 2007; received in revised form 8 March 2008; accepted 25 March 2008.

Abstract

Objective

The aim of this study was to investigate the influence of a fiber post on the fracture mechanics of zirconia crowns inserted over endodontically treated teeth with different extent of coronal damage.

Methods

Endodontically treated human molars with three types of coronal damage received fiber posts before cementation of zirconia-veneered crowns. Controls received composite resin cores without fiber posts. The specimens were loaded to failure and fractographically examined using a scanning electron microscope (SEM).

Results

Statistical analysis revealed that specimens with fiber posts demonstrated significantly higher failure loads and favorable fracture pattern compared to the controls. At fractographic analysis, specimens with fiber posts demonstrated delamination of the veneer ceramic from intact zirconia under structure. Meanwhile, the specimens that were restored without a fiber post demonstrated micro-cracking of the composite core build-up resulting in loss of the support under the zirconia crowns which was responsible for the initiation of radial crack and catastrophic damage.

Conclusions

Within the limitation of this study, the insertion of fiber post improved the support under zirconia crowns which resulted in higher fracture loads and favorable failure type compared to composite core build-up.

Keywords: Fiber post, Zirconia crown, Fracture resistance, Failure pattern, Fractography