Sadiq Ameen Hakim Almayali

Aim: The paper aimed to evaluate using a modified flask on surface hardness and roughness, flexural, and tensile strength for heat-polymerized acrylic resin. Materials and methods: 80 specimens of heat-polymerized acrylic resin were prepared, and divided into two main groups. This division was followed type of flask that was used for processing the acrylic. 40 specimens of the first group (control) were prepared using a regular flasking technique, and the remaining 40 specimens were prepared using a modified flask which represented a second (testing) group. Then each group subdivided into another four groups according to the test will be done (10 specimens for each test group) hardness, flexural strength, tensile strength, and surface roughness, a statistical analysis with a p-value ≤ 0.05 was carried out for values obtained. Results: The amount of surface hardness (shore D) were 33.14 ± 2.04 and 29.57 ± 1.23; the flexural strengths (MPa) were 107.3 ± 9.54 and 89.92 ± 2.05; the tensile strengths (MPa) were 31.30 ± 8.46 and 15.50 ± 2.46; and surface roughness (μm) values were 1.15 ± 0.556 and 0.78 ± 0.29 for the experimental and control groups, respectively. There were noticeable effects on surface hardness, flexural and tensile strength with p-value < 0.05, and unnoticeable effects on surface roughness when compared between experimental and control groups. Conclusion: According to the result of this study, the mechanical properties of heat-polymerized acrylic resin were improved using a modified flask with a new metal plate. © 2025, Ain Shams University, Faculty of Dentistry. All rights reserved.

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