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Porosity, Micro-Hardness and Morphology of White and Gray Portland Cements in Relation to Their Potential in the Development of New Dental Filling Materials

Purpose: Portland cements may be used in dentistry due to their excellent biocompatibility, sealing ability and potential osteogenic induction. The aim of the present study was to identify the structural and physical properties of two basic Portland cements for their development as potential new dental filling materials. Methods: The two Portland cements, White Portland (WPC) and Gray Portland (GPC), were mixed with distilled water and immediately incubated in water (H2O) or Phosphate Buffered Saline (PBS) at 37°C. Knoop Micro-hardness, volumetric mass/porosity and SEM surface analysis were performed at different time intervals (7, 14, 28 days). Results: Knoop micro-hardness, volumetric mass \ porosity and SEM evaluations performed at different time intervals (7, 14, 28 days) revealed that the WPC had the highest micro-hardness, whereas Portland cement GPC presented higher level of porosity in the early stages of the setting phase. Conclusion: The different structural and physical characteristics showed by the two basic Portland cements should be taken in consideration during the identification of the most potential applications for the development of new dental filling materials.