Influence of endodontic posts on the fracture behavior of crowned premolars with class II cavities

Nothdurft, F.P.; Seidel, E.; Gebhart, F.; Naumann, M.; Motter, P.J.; Pospiech, P.R.

doi:10.1016/j.jdent.2008.01.007

« Previous Next »Journal of Dentistry
Volume 36, Issue 4 , Pages 287-293, April 2008

Influence of endodontic posts on the fracture behavior of crowned premolars with class II cavities

F.P. Nothdurft
- Department of Prosthetic Dentistry and Dental Materials Sciences, Dental School and Clinics, Saarland University, Homburg/Saar, Germany
- Corresponding author at: Department of Prosthetic Dentistry and Dental Materials Sciences, Saarland University, Homburg Campus, Bldg. 71.2, 66421 Homburg/Saar, Germany. Tel.: +49 6841 1624901; fax: +49 6841 1624952.
E. Seidel
- Department of Orthodontics, University of Munich, Munich, Germany
F. Gebhart
- Department of Orthodontics, University of Munich, Munich, Germany
M. Naumann
- Institute of Dental Prosthodontics, Geriatric Dentistry and Cranio-Mandibular Disorders, Charite, University Medical School, Campus Virchow, Berlin, Germany
P.J. Motter
- Department of Prosthetic Dentistry and Dental Materials Sciences, Dental School and Clinics, Saarland University, Homburg/Saar, Germany
P.R. Pospiech
- Department of Prosthetic Dentistry and Dental Materials Sciences, Dental School and Clinics, Saarland University, Homburg/Saar, Germany

Received 2 November 2007; received in revised form 10 January 2008; accepted 12 January 2008.

Abstract

Aim

The aim of the study was to evaluate the influence of different posts and types of cementation on the fracture load and fracture mode of crowned, endodontically treated premolars with class II cavities in an ex vivo setting.

Methods

Forty-eight single-rooted human premolars were endodontically treated and prepared with standardized MO (mesio-occlusal) cavities and a circular chamfer preparation. Eight teeth each received either no posts or were restored with screws (BKS), glass fiber posts (DentinPost), or quartz fiber posts (DT Light SL). Sixteen teeth were restored with zirconium dioxide posts (CeraPost). BKS-screws and eight zirconium dioxide posts were cemented conventionally with glass ionomer cement; Panavia F was used for all others. The specimens were restored with composite cores and crowns cast from a non-precious metal. Eight sound premolars served as the controls. After thermomechanical fatigue testing, the samples were loaded until fracture occurred at an angle of 45°. All specimens were evaluated for fracture lines.

Results

The sound teeth showed the significant highest fracture load (792.50±210.01N). Conventionally cemented zirconium dioxide posts showed the lowest fracture load (327.00±45.84N); the highest fracture load occurred with quartz fiber posts (421.75±90.19N). Only the difference between these two groups was statistically significant. With glass fiber posts and conventionally cemented zirconia posts, restored teeth failed mostly in an “unfavourable” mode.

Conclusions

With respect to the fracture load, there was no statistical difference between the restoration of non-vital premolars with class II cavities with crowns and posts or crowns alone.

Keywords: Post and core, Fracture resistance, Fracture mode, Ex vivo