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Objectives: This study compared the flexural strength of three denture base materials when processed under long-curing and short-curing techniques.
Material and methods: Three denture base materials (SR Triplex Hot, Probase Hot and SR Ivocap High Impact) were polymerized in long- and short- curing procedures. Twelve rectangular specimens (10mm x 64mm x 3.3mm) of each material were prepared according to ISO 20795, and stored in distilled water at 37oC for 48 hours. The three-point bending test with a 5 mm/min crosshead speed was carried out using a universal testing machine.
Results: The mean and standard deviation values of flexural strength of SR Triplex Hot, ProBase Hot and SR Ivocap High Impact cured by long-curing procedure were 78.8±2.5, 78.9±2.8 and 73.2 ±4.6 MPa, respectively. Of those cured by short-curing procedure were 76.0±2.6, 77.5±3.0 and 68.1±2.8 MPa, respectively. Two-way ANOVA (∝=0.05) showed that there was no interaction between the two variable – material and curing time. The flexural strengths of SR Triplex Hot and ProBase Hot were significantly higher than those of SR Ivocap High Impact (p<0.05). In addition, the flexural strengths of materials subjected to long-curing procedure were significantly higher than those processed by short-curing procedure (p<0.05).
Conclusion: Flexural strength of SR Triplex Hot and ProBase Hot were higher than that of SR Ivocap High Impact. Longer curing time resulted in higher flexural strength of the denture base materials.
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