کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1422871 | 986463 | 2010 | 8 صفحه PDF | دانلود رایگان |
ObjectivesThis investigation evaluated the flexural properties of two composite resins, and the influence of unidirectional glass fiber reinforcements, with and without pre-tensioning.MethodsTwo composite resins (Q: Quixfil and A: Adoro) were used to fabricate 2 mm × 2 mm × 25 mm beams (N = 10), reinforced with two fiber bundles along the long axis of the beam and pre-tensioned under a load equivalent to 73.5% of its tensile strength (groups QPF and APF). In two other experimental groups, the bundles were similarly positioned but without pre-tension (groups QF and AF). Two more groups were included without fiber reinforcement (control groups Q and A). After 24 h storage, specimens were subjected to a three-point flexural bending test to establish the flexural module, the deflection at initial failure and the flexural strength. Data were analyzed using a two-way analysis of variance (composite resin system and fiber reinforcement type) and the Tukey HSD post hoc tests (α = .05).ResultsThe results showed that prestressing increased the flexural module of Adoro specimens (p < .001) but not Quixfil (p = .17). Prestressed beams reached greater deflection at initial failure than those conventionally reinforced (p < .001), namely .85–1.35 mm for Adoro and .66–.90 mm for Quixfil. Prestressing also significantly increased the flexural strength of beams (p < .001) in both Adoro and Quixfil groups, from 443.46 to 569.15 MPa and from 425.47 to 568.00 MPa, respectively.SignificancePre-tensioning of unidirectional glass fibers increased both deflection until initial failure and flexural strength of Quixfil and Adoro composite resins, however, with limited effects on the flexural modulus.
Journal: Dental Materials - Volume 26, Issue 2, February 2010, Pages 118–125