الفهرس | Only 14 pages are availabe for public view |
Abstract Abstract Purpose: This study evaluates the marginal adaptation, fracture resistance and deflection in short and long spans dental fixed prosthesis. Materials and methods: 140 fabricated interim FPD were divided into two main groups: group I: short-span FPD (n=70) & group II: long-span FPD (n=70). Each group was subdivided into seven subgroups (n=10) for each according to interim materials: Subgroup A: CAD-CAM composite blocks, Subgroup B: Chemicalcured acrylic resin material, as control, Subgroup C: zirconia powder reinforced acrylic resin (experimental), Subgroup D: Chemical-cured composite resin, Subgroup E: Dual-cured composite resin, Subgroup F: Light cured composite resin reinforced with polyethylene fibers & Subgroup G: Light cured composite resin reinforced with glass fibers. Marginal adaptation was measured using USB Digital microscope. Fracture resistance and deflection values were evaluated by three point bending test using ”Instron testing machine”. Results: Long-span FPD recorded higher marginal gap than short-span FPD (mean: 47.88 μm vs 43.78 μm, p<0.001). When testing the marginal gaps of different tested materials of the prepared interim FPDs of short and long span FPD groups, the highest mean value was recorded for zirconia powder reinforced acrylic resin (50.48 μm & 64.26 μm) respectively and the lowest mean value was recorded for polyethylene fiber reinforced composite ”Construct®” (33.99 μm & 30.69 μm) respectively. Long-span FPD recorded higher deflection than short-span FPD (mean: 5.18 mm vs 3.49 mm, p<0.001).When testing deflection with short and long span FPD groups, the highest mean value was recorded for polyethylene fiber reinforced composite ”Construct®” (9.80 mm & 7.18 mm) respectively, while the lowest deflection mean value was recorded for dual-cured composite resin ”TemSpan TM” (2.12 mm) for short span FPD group. But the lowest deflection mean value was recorded for CAD-CAM composite blocks ”VITA-CAD Temp” (3.39 mm) for long span FPD group. Short-span FPD recorded higher fracture resistance than long-span FPD (mean: 65.18 Mpa vs 52.42 Mpa, p<0.05). When testing fracture resistance with short span FPD group, the highest fracture resistance mean value was recorded for zirconia powder reinforced acrylic resin (141.7 Mpa) and lowest mean value was recorded for chemical-cured composite resin ”ProtempTM4” (20.86 Mpa). When testing fracture resistance with long span FPD group, the highest mean value was recorded for CAD-CAM composite blocks ”VITA-CAD Temp” (102.1 Mpa) and the lowest mean value was recorded for chemical-cured composite resin ”ProtempTM4” (20.33 Mpa). |