IADR Abstract Archives
Characterisation of Hybrid Calcium Aluminate-Glass Ionomer Cement
Objectives: To characterize setting reaction, the pH evolution, determine working/setting time and test the compressive strength of commercial calcium aluminate-glass ionomer cement (CaAl-GIC).
Methods: Two dental luting agents were used for this study, Ceramir Crown & Bridge® (Doxa Dental, Uppsala, Sweden) and Ketac Cem Maxicap® (3M ESPE, MN, USA). The characterization of setting reaction was performed by Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy. The crystalline phases of the CaAl-GIC were characterized by X-ray diffraction (XRD). Changes in pH during setting were measured using membrane pH electrode where deionized water exists on the surface of the cement samples. The working and setting times were identified using oscillating rheometer. The compressive strength was measured according to the ISO: 9917-1 using a universal mechanical testing machine.
Results: The XRD pattern of the unreacted powder of the hybrid cement showed crystalline phases of monocalcium aluminate (CaAl2O4) and demonstrated the presence of strontium fluoride. The FTIR spectra of the CaAl-GIC were not much dissimilar from the spectrum of GIC which indicates the presence of the GIC elements in this hybrid cement. However, the presence of AlO4 tetrahedra and AlO6 octahedra in the crystalline environment are uniquely characteristic for CaAl-GIC. The pH changes of CaAl-GIC over a 24 hours period increased as a function of time, and the cement showed an alkalinity after 24 hours with the pH value of 11.50(±0.20). The average working and setting times for CaAl-GIC were determined to be 1.21(±0.06) min. and 1.77(±0.03) min. respectively. The mean compressive strengths of CaAl-GIC at 24 hrs. and four weeks was 111.15(±26.75) and 85.63(±18.97) MPa respectively, which exceeded the minimum ISO requirements.
Conclusions: This study showed that the hybrid CaAl-GIC possess favourable properties and have potentials to expand its clinical applications as a dental biomaterial.
Methods: Two dental luting agents were used for this study, Ceramir Crown & Bridge® (Doxa Dental, Uppsala, Sweden) and Ketac Cem Maxicap® (3M ESPE, MN, USA). The characterization of setting reaction was performed by Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy. The crystalline phases of the CaAl-GIC were characterized by X-ray diffraction (XRD). Changes in pH during setting were measured using membrane pH electrode where deionized water exists on the surface of the cement samples. The working and setting times were identified using oscillating rheometer. The compressive strength was measured according to the ISO: 9917-1 using a universal mechanical testing machine.
Results: The XRD pattern of the unreacted powder of the hybrid cement showed crystalline phases of monocalcium aluminate (CaAl2O4) and demonstrated the presence of strontium fluoride. The FTIR spectra of the CaAl-GIC were not much dissimilar from the spectrum of GIC which indicates the presence of the GIC elements in this hybrid cement. However, the presence of AlO4 tetrahedra and AlO6 octahedra in the crystalline environment are uniquely characteristic for CaAl-GIC. The pH changes of CaAl-GIC over a 24 hours period increased as a function of time, and the cement showed an alkalinity after 24 hours with the pH value of 11.50(±0.20). The average working and setting times for CaAl-GIC were determined to be 1.21(±0.06) min. and 1.77(±0.03) min. respectively. The mean compressive strengths of CaAl-GIC at 24 hrs. and four weeks was 111.15(±26.75) and 85.63(±18.97) MPa respectively, which exceeded the minimum ISO requirements.
Conclusions: This study showed that the hybrid CaAl-GIC possess favourable properties and have potentials to expand its clinical applications as a dental biomaterial.