#Flexture test with three point loading iso

RESULTS: Milled resins showed significantly higher values for flexural strength, elastic modulus, and surface hardness, followed by HP and then 3D-printed resins (p < 0.001). The means and standard deviations were calculated, followed by one-way ANOVA and Tukey post-hoc test (α = 0.05). Scanning electron microscope was used to evaluate the surface morphology of the fractured specimens. The dimensions for hardness test were 15 × 10 × 2.5 ± 0.2 mm.

#Flexture test with three point loading iso

To test flexural properties, the specimens were fabricated according to ISO 20795-1:2013 standards (64 × 10 × 3.3 ± 0.2 mm). Flexural strength and elastic modulus of the specimens were evaluated by 3-point bending test and surface hardness by Vickers hardness test. The specimens were divided into 6 groups according to the type of denture base material (n = 20/material) (10/flexural properties and 10/hardness). MATERIALS AND METHODS: A total of 120 specimens were fabricated from heat-polymerized acrylic resin (HP), milled resin (Avadent and IvoCad), and 3D-printed resin (ASIGA, FormLabs, and NextDent). PURPOSE: To compare flexural strength, elastic modulus, and surface hardness of computer aided design and computer aided manufacturing CAD-CAM milled, 3D-printed, and heat-polymerized denture base resins. Autoclave polymerization significantly increased the flexural strength, impact strength, and hardness of unmodified PMMA and hardness of 0.5% ND group. Conclusion: The addition of ND at low concentration increased the elastic modulus and flexural strength of conventionally and autoclave polymerized denture base resin. Hardness decreased significantly with 0.25%ND in group II. Impact strength showed no significant change with the addition of ND in groups I and II (p=0.227, p=0.273), as well as surface hardness in group I (p=0.143). Elastic modulus increased at 0.1% ND for both groups (p=0.004, p=0.373), but the increase was statistically significant for group I only. Results: ND addition significantly increased the flexural strength of groups I and II (p < 0.001, p=0.003) it was highest (128.8 MPa) at 0.25% ND concentration for group I and at 0.1% for group II. ANOVA and post hoc Tukey test were used for data analysis (α = 0.05). The bonding and interaction between the PMMA and ND particles were analyzed by the Fourier-transform infrared (FTIR) spectroscope. Surface hardness was measured by a hardness tester with a Vickers diamond. A scanning electron microscope (SEM) was used to analyze the fractured surfaces. The impact strength, flexural strength, and elastic modulus were tested using the Charpy-type impact-testing machine and three-point bending test, respectively. The specimens were divided equally into group I: conventionally polymerized PMMA by water bath and group II: polymerized by the autoclave. Methods: A total of 240 heat polymerized PMMA were fabricated with low ND concentrations of 0.1%, 0.25%, and 0.5%, and unmodified as control. Purpose: Investigate the effect of low nanodiamond (ND) addition and autoclave polymerization on the flexural strength, impact strength, and hardness of polymethylmethacrylate (PMMA) denture base.