Maghraby, A., Shalaby, Y., Alabbassy, F., Azer, A. (2023). FRACTURE RESISTANCE OF CAD/CAM ONE-PIECE AND TWO-PIECE POST-CORE-CROWN RESTORATIONS USING TWO DIFFERENT MATERIALS (IN VITRO STUDY). Alexandria Dental Journal, 48(1), 146-153. doi: 10.21608/adjalexu.2021.85756.1208
Ahmed Maghraby; Yousria Atteya Shalaby; Fayza Hassan Alabbassy; Amir Shoukry Azer. "FRACTURE RESISTANCE OF CAD/CAM ONE-PIECE AND TWO-PIECE POST-CORE-CROWN RESTORATIONS USING TWO DIFFERENT MATERIALS (IN VITRO STUDY)". Alexandria Dental Journal, 48, 1, 2023, 146-153. doi: 10.21608/adjalexu.2021.85756.1208
Maghraby, A., Shalaby, Y., Alabbassy, F., Azer, A. (2023). 'FRACTURE RESISTANCE OF CAD/CAM ONE-PIECE AND TWO-PIECE POST-CORE-CROWN RESTORATIONS USING TWO DIFFERENT MATERIALS (IN VITRO STUDY)', Alexandria Dental Journal, 48(1), pp. 146-153. doi: 10.21608/adjalexu.2021.85756.1208
Maghraby, A., Shalaby, Y., Alabbassy, F., Azer, A. FRACTURE RESISTANCE OF CAD/CAM ONE-PIECE AND TWO-PIECE POST-CORE-CROWN RESTORATIONS USING TWO DIFFERENT MATERIALS (IN VITRO STUDY). Alexandria Dental Journal, 2023; 48(1): 146-153. doi: 10.21608/adjalexu.2021.85756.1208
FRACTURE RESISTANCE OF CAD/CAM ONE-PIECE AND TWO-PIECE POST-CORE-CROWN RESTORATIONS USING TWO DIFFERENT MATERIALS (IN VITRO STUDY)
2Conservative Dentistry Department, Faculty of Dentistry, Alexandria University
3Dental Biomaterials Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt
4Conservative Dentistry Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt.
Abstract
Introduction: Restoring teeth that lost significant percentage of coronal structure necessitates using post and core before crown coverage. The most common systems are the one-piece post and core and the two-element system. Recently the one-piece restoration, the Richmond crown, could be milled using CAD/CAM to rehabilitate severely damaged teeth. A variety of aesthetic materials have become available for milling. Aim: To compare between the fracture resistance (FR) of one-piece and two-piece post-core-crown restorations using two different materials; hybrid ceramic (HC) and zirconia (ZR). Materials and methods: The study was conducted on 20 artificial maxillary canines. The teeth were prepared then randomly divided as follows: Group I, one-piece post-crown restoration (N=10) which were further subdivided into Subgroup IA: hybrid ceramic and Subgroup IB: zirconia. Group II, two-piece post-core and cemented crown (N=10) which were also subdivided into Subgroup IIA: hybrid ceramic, and Subgroup IIB: zirconia. The specimens were subjected to fracture resistance testing using universal testing machine followed by analyzing the failed specimens with the stereomicroscope. Results were statistically analyzed using F test (ANOVA) and Post-hoc test (Tukey), significance was judged at 5%. Results: The FR values (mean±SD in Newtons) were 386.6 ± 25.78N for subgroup IA, 522.2 ± 70.56N for subgroup IB, 429.6 ± 91.87N for subgroup IIA, and 648.6 ± 93.37N for subgroup IIB with no significant difference in FR between the one-piece and the two-piece restorations using either HC or Zr. Conclusion: The one-piece post-crown restorations showed good performance regarding fracture resistance.