Fracture load and shear stress of prefabricated glass fiber posts

Keywords: Glass, Materials testing, Stress, mechanical, Flexural strength.


Aim: This study evaluated the fracture load and pattern failure of different prefabricated glass fiber posts (GFPs) of the same diameter. Methods: Seventy-eight (n=13 for six groups) GFPs of 1.6 mm coronal diameter of different brands were evaluated— Exacto (Angelus), Power Post (BM4), White Post DC (FGM), HiRem (Overfibers), MAQ (Maquira), and SD (Supordont). The posts were subjected to fracture load testing (45° of inclination and 1 mm/min until fracture). Each factor (load (N) and shear stress (MPa)) was analyzed separately using one-way ANOVA followed by the Tukey test (α=0.05). Results: The type of failure was evaluated on a stereomicroscope (×10). The Power Post samples presented higher values of fracture load (p<0.001) followed by Maquira fiber post, White Post , HiRem, Superpost, and the Exacto posts. The failure pattern observed was intralaminar mode II in-plane shear, such as a failure occur parallel to fibers. Conclusion: Despite the same diameter of GFPs, the fracture load and shear resistance were brand-dependent.


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Author Biographies

Helder Callegaro Velho, Franciscan University
School of Dentistry, Franciscan University, Santa Maria, Rio Grande do Sul, Brazil.
Paolo Baldissara, University of Bologna
Department of Biomedical and Neuromotor Sciences, Unit of Odontostomatological Sciences, Division of Prosthodontics, Alma Mater Studiorum, University of Bologna, Bologna, Italy.
Jovito Adiel Skupien, Franciscan University
Division of Conservative Dentistry, School of Dentistry, Franciscan University, Santa Maria, Rio Grande do Sul, Brazil.
Vinicius Felipe Wandscher, Franciscan University
Division of Prosthodontics, School of Dentistry, Franciscan Unviersity, Santa Maria, Rio Grande do Sul, Brazil.


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How to Cite
Velho, H. C., Baldissara, P., Skupien, J. A., & Wandscher, V. F. (2019). Fracture load and shear stress of prefabricated glass fiber posts. Brazilian Journal of Oral Sciences, 18, e191561.