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Published on: December 20, 2024
Fracture strength of teeth restored with all-ceramic posts and cores
Wiebke Friedel1, Matthias Kern
1Department of Prosthodontics, Propaedeutic, and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany.
Objective:
The purpose of this in vitro investigation was to evaluate the fracture strength of endodontically treated teeth restored with different all-ceramic posts and cores.
Method And Materials:
Seventy-two endodontically treated human maxillary central incisors were divided into 3 groups with 24 teeth each and restored with 1 of the following methods: prefabricated zirconia ceramic posts and resin composite buildups; zirconia ceramic posts and copy-milled alumina ceramic cores (2-piece technique), or copy-milled all-ceramic posts and cores made from a zirconia-reinforced glass-infiltrated alumina ceramic (1-piece technique). Each group was divided into 3 subgroups of 8 samples each, consisting of teeth that did not receive crown restorations and were stored for 60 days, teeth restored with all-ceramic crowns and stored for 60 days, and teeth restored with all-ceramic crowns and subjected to 1.2 million loading cycles with 30 N in a chewing simulator.
Results:
The mean fracture strengths ranged from 205 to 522 N. Prefabricated zirconia posts and resin composite buildups showed a statistically significantly lower fracture strength after chewing simulation than teeth restored with prefabricated zirconia posts and alumina ceramic cores.
Conclusion:
All-ceramic posts and cores made with the 2-piece technique showed promising fracture strengths under the tested conditions.
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