Comparison of hardness, compressive strength and radiopacitiy of Biodentine with GlassIonomer cement .
Objectives: The hardness, compressive strength and radio-opacity values of the two materials were evaluated and compared using standardized testing methodology Methods: Hardness For measurements of Vickers microhardness (HV), Biodentine and GC FUGI IX were mixed and ten samples of each cement type were produced. The specimens were inspected and then then trimmed using silicone carbide paper (600 grit).Vickers hardness was calculated using a diamond shaped indenter and values of VHN were recorded. Radiopacity Samples were prepared using stainless steel ring mould. Ten samples were produced and allowed to set for 24 h for each cement. All samples were placed on a dental x-ray sensor (Kodak ) together with an aluminium step wedge (1–9 mm). The x-ray exposures were made using a Sirona DS x-ray. The gray pixel value on the radiograph, of each step in the step-wedge was determined using an imaging program, Microsoft Paint as a number between 0 and 255 with 0 representing pure black and 255 pure white. The gray pixel values of the cement specimens were then determined using the imaging program, and plugged into this equation to calculate the equivalent radiopacity of the cement sample, expressed in mm of aluminum. Compressive strength Cylindrical specimen were prepared to determine the compressive strength. Twelve cylinders were prepared from each material type and were cured immersed in distilled water at 37 ◦C for 7 days. The specimens were tested in compression using a 15 KN compression testing jig in a universal testing machine attached to a console and data logging.. The compressive strength value was recorded for each material and specimen. Results: Biodentine has hardness and compressive strength values of around 48 VHN and 68 MPa respectively. The results indicate that biodentine can be employed to replace dentine as its hardness and compressive strength values are close to dentin although GIC may have better mechanical properties in comparison. Glass ionomer cements are more radio-opaque as compared with Biodentine had a radiopacity value which ranged between 4 and 5 mm aluminium. Conclusions: biodentine can be employed to replace dentine. Glassionomer cements are more radiopaque.