IADR Abstract Archives
Mechanical Properties of Translucent Multilayered Zirconia Materials
Objectives: To evaluate the biaxial flexural strengths and 3-point bend flexural strengths of three different types of commercially available zirconia.
Methods: Forty-five sectioned disks of ADML A-Dark Multilayered zirconia (conventional, n=15), STML Super Translucent Multilayered zirconia (intermediate translucency, n=15), and UTML Ultra Translucent Multilayered zirconia (high translucency, n=15) zirconia were prepared by core-drilled cylinders from a disc puck (Katana from Kuraray). Forty-four sectioned bars of ADML, STML, and UTML zirconia were prepared by sectioning bars from the remaining disk pucks. The sintering was completed according to the manufacturers recommendations in a furnace (Zircar Hot Spot 110) with a slow firing cycle ramping to 1500°C in 2.25 hours, soaked for 4.5 hours, then cooled to 90°C in 2.25 hours. The sectioned specimens were prepared to compensate for 20% shrinkage in order to get the desired fully-sintered disk dimensions of 1.5mm thickness and 16.3 mm in diameter and bar dimensions of 2x3.5x15mm. The disks were tested in biaxial flexural fixture and the bars were tested in 3-point bend flexural fixture using a universal testing machine (Instron 5566A) until complete fracture, with failure recorded at max load (MPa). Flexural strength data were analyzed with ANOVA and Tukey HSD using JMP Pro 13.2.
Results: The mean biaxial flexural strengths for ADML, STML, and UTML were as follows: 931.76 ± 108.94 MPa, 758.01 ± 80.00 MPa, 654.92 ± 40.78 MPa. The mean 3-point bend flexural strengths for ADML, STML, and UTML were as follows: 1169.72 ± 244.16 MPa, 762.16 ± 200.96 MPa, 464.28 ± 153.86 MPa. ADML had significantly higher biaxial flexural strength and 3-point bend flexural strength than others. UTML had the significantly lower biaxial flexural strength and 3-point bend flexural strength than others.
Conclusions: The increase in translucency decreased the biaxial flexural strength and 3-point bend flexural strength of the zirconia material.
Methods: Forty-five sectioned disks of ADML A-Dark Multilayered zirconia (conventional, n=15), STML Super Translucent Multilayered zirconia (intermediate translucency, n=15), and UTML Ultra Translucent Multilayered zirconia (high translucency, n=15) zirconia were prepared by core-drilled cylinders from a disc puck (Katana from Kuraray). Forty-four sectioned bars of ADML, STML, and UTML zirconia were prepared by sectioning bars from the remaining disk pucks. The sintering was completed according to the manufacturers recommendations in a furnace (Zircar Hot Spot 110) with a slow firing cycle ramping to 1500°C in 2.25 hours, soaked for 4.5 hours, then cooled to 90°C in 2.25 hours. The sectioned specimens were prepared to compensate for 20% shrinkage in order to get the desired fully-sintered disk dimensions of 1.5mm thickness and 16.3 mm in diameter and bar dimensions of 2x3.5x15mm. The disks were tested in biaxial flexural fixture and the bars were tested in 3-point bend flexural fixture using a universal testing machine (Instron 5566A) until complete fracture, with failure recorded at max load (MPa). Flexural strength data were analyzed with ANOVA and Tukey HSD using JMP Pro 13.2.
Results: The mean biaxial flexural strengths for ADML, STML, and UTML were as follows: 931.76 ± 108.94 MPa, 758.01 ± 80.00 MPa, 654.92 ± 40.78 MPa. The mean 3-point bend flexural strengths for ADML, STML, and UTML were as follows: 1169.72 ± 244.16 MPa, 762.16 ± 200.96 MPa, 464.28 ± 153.86 MPa. ADML had significantly higher biaxial flexural strength and 3-point bend flexural strength than others. UTML had the significantly lower biaxial flexural strength and 3-point bend flexural strength than others.
Conclusions: The increase in translucency decreased the biaxial flexural strength and 3-point bend flexural strength of the zirconia material.