TY - JOUR ID - 13375 TI - Comparison between Biaxial Flexural Strength and Microstructure of Polished and Glaze-Fired Specimens of Zirconia Lithium Silicate Glass Ceramic JO - Journal of Dental Materials and Techniques JA - JDMT LA - en SN - 2322-4150 AU - Attaallah, Alaa M. AU - Zayed, Eman M AU - Dabees, Salma M AU - Ashour, Youssef Y AU - fahmy, Amal Ezz-Eldin AD - Dental Student, Faculty of Dentistry, Pharos University, Alexandria, Egypt AD - 1Dental Student, Faculty of Dentistry, haros University, Alexandria, Egypt AD - Assistant Lecturer of Fixed Prosthodontics, Faculty of Dentistry, Pharos University, Alexandria, Egypt AD - Professor of Dental Biomaterials, Faculty of Dentistry, Pharos University, Alexandria, Egypt Y1 - 2019 PY - 2019 VL - 8 IS - 3 SP - 114 EP - 120 KW - Celtra Duo KW - Piston-on-three-ball KW - CAD/CAM KW - ZLS DO - 10.22038/jdmt.2019.13375 N2 - Introduction: There has been a growing interest in glass ceramic systems with good esthetics, high fracture resistance, bonding durability, and simplified fabrication techniques using CAD/CAM. The aim of this study was to compare flexural strength in "polished" and "glazed and fired" specimens of zirconium lithium silicate (ZLS) CAD/CAM blocks Celtra Duo. Methods: A total of 14 specimens of Celtra Duo (Dentsply Sirona, Germany) were designated and equally divided into two groups, including group I (n=7; as polished) and group II (n=7; as glazed and fired) according to the manufacturers’ instructions. Then biaxial flexural strength was tested according to ISO 6872 using a universal testing machine and piston-on-three-ball method after polishing, glazing, and firing. The fractured surfaces and microstructure were observed by scanning electron microscope (Jeol/GSM5300). Data were then statistically analyzed using SPSS software (version 20.0). Results: There were statistically significant differences in biaxial flexural strength between a polished and glaze-fired specimen of ZLS glass ceramic discs as biaxial flexural strength was lower in polished specimens (mean±standard deviation: 158.7±21.67 MPa), while the glazed specimens showed higher biaxial flexural strength (mean±standard deviation: 261.5±31.89 MPa). Conclusion: Glazing and firing of Celtra Duo specimens increased biaxial flexural strength significantly in comparison to polishing with no significant change in the microstructure.     UR - https://jdmt.mums.ac.ir/article_13375.html L1 - https://jdmt.mums.ac.ir/article_13375_c8fbf9b1c7cf3c9494a638f668c83bd2.pdf ER -