Amir Nageeb - Profile on Academia.edu (original) (raw)
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Universidad Interamericana De Panama
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Objectives: There has been a growing interest in glass ceramic systems with good esthetics, high ... more Objectives: There has been a growing interest in glass ceramic systems with good esthetics, high fracture resistance and bonding durability, and simplified fabrication techniques using CAD/CAM. The aim of this study is to compare flexural strength "as polished" and "as glazed and fired" specimen's of zirconium lithium silicate (ZLS) CAD/CAM blocks Celtra Duo. Materials and Methods: 14 specimens of (Celtra Duo, dentsupply serona, Germany) were designated and equally divided into two groups, group I (n=7) (as polished) and group II (n=7) (as glazed and fired) according to manufacture instruction. then biaxial flexural strength was tested according to ISO 6872 using a universal testing machine with 14 sliced disc form specimens after polishing and after glazing and firing. The crystalline structures were observed by scanning electron microscope SEM (Jeol/GSM5300). Data were then statistically analyzed using (IBM SPSS software package version 20.0). Results: There were statistically significant differences in biaxial flexural strength between polished and glazed and fired specimen of the zirconium lithium silicate glass ceramics (ZLS) discs 2 as polished specimens were less in biaxial flexural strength (mean±SD = 158.7±21.67) while the glazed specimens were more in biaxial flexural strength (mean±SD = 261.5±31.89). Conclusions: Glazing and firing of Celtra Duo specimens increases the biaxial flexural strength significantly over the polishing with no significant change in microstructure.
Objectives: There has been a growing interest in glass ceramic systems with good esthetics, high ... more Objectives: There has been a growing interest in glass ceramic systems with good esthetics, high fracture resistance and bonding durability, and simplified fabrication techniques using CAD/CAM. The aim of this study is to compare flexural strength "as polished" and "as glazed and fired" specimen's of zirconium lithium silicate (ZLS) CAD/CAM blocks Celtra Duo. Materials and Methods: 14 specimens of (Celtra Duo, dentsupply serona, Germany) were designated and equally divided into two groups, group I (n=7) (as polished) and group II (n=7) (as glazed and fired) according to manufacture instruction. then biaxial flexural strength was tested according to ISO 6872 using a universal testing machine with 14 sliced disc form specimens after polishing and after glazing and firing. The crystalline structures were observed by scanning electron microscope SEM (Jeol/GSM5300). Data were then statistically analyzed using (IBM SPSS software package version 20.0). Results: There were statistically significant differences in biaxial flexural strength between polished and glazed and fired specimen of the zirconium lithium silicate glass ceramics (ZLS) discs 2 as polished specimens were less in biaxial flexural strength (mean±SD = 158.7±21.67) while the glazed specimens were more in biaxial flexural strength (mean±SD = 261.5±31.89). Conclusions: Glazing and firing of Celtra Duo specimens increases the biaxial flexural strength significantly over the polishing with no significant change in microstructure.