Том 7 (2004)

The effect of internal fiber arrangement on the delamination failure in hybrid composite dental prostheses

S.R. Dyer2,3, L.V.J. Lassila3, P.K. Vallittu3

2Oregon Health and Sciences University, School of Dentistry, Department of Restorative Dentistry, Division of Biomaterials and Biomechanics, Portland, Oregon, 97239, USA
3University of Turku, Institute of Dentistry, Department of Prosthetic Dentistry and Biomaterials, Turku, FIN-20520, Finland

Objective: To test dental fiber-reinforced composite (FRC) substructure arrangements within a bi-layer beam on the load to initial (IF) and final failure (FF) in a modified mode II delamination test. Methods: Three groups of FRC and particulate reinforced composite (PRC) were tested: PE (Ultra high molecular weight polyethylene ribbon, Connect, and BelleGlass, Kerr), W (woven E-glass, Vectris Frame, and Targis, Ivoclar), and U (unidirectional R-glass, Vectris Pontic, and Targis, Ivoclar). Twelve specimens were fabricated by placing an FRC layer into a 25x6x0.75 mm3 mold. PRC (10x6x0.75 mm3) was added to the specimen center. The FRC was placed into unpolymerized PRC layer at 3 depths to the veneer surface: 0 % (750 mm), 50 % (300 mm), or 100 % (< 10 mm). After light-polymerization, the specimens were standardized and then stored 1 week in 37 °C water. Four specimens were randomly selected for sectioning/pre-test evaluation. The remaining 8 specimens (= n) were loaded in a static 4-point bend test (20 mm upper/ 10 mm lower spans) veneer side down until failure (recording IF and FF). A failure ratio (FR) was developed (IF/FF x 100). Means and standard deviations (SD) were calculated (ANOVA, Tukey post hoc, p < 0.05). Results: No position of PE fiber increased the load to elicit IF. For the woven E-glass and unidirectional R-glass, the 50 % fiber position increased the load to IF. Conclusion: Glass fiber positions with 50 % penetration into the PRC significantly increased the load to IF in a modified mode II delamination.

стр. 119 – 122

Образец цитирования:
S.R. Dyer, L.V.J. Lassila, P.K. Vallittu  The effect of internal fiber arrangement on the delamination failure in hybrid composite dental prostheses // Физ. мезомех. - 2004. - Т. 7. - № Спец2. - С. 119-122