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    Bonding of resin composite luting cements to zirconium oxide by two air-particle abrasion methods
    (Operative Dentistry Inc, 2006) Kumbuloglu, O; Lassila, LVJ; User, A; Vallittu, PK
    Objective: This study evaluated the shear bond strength of two resin composite luting cements to zirconium oxide ceramic substrate using two air-particle abrasion methods. Methods: Two resin composite cements, RelyX Unicem (3M ESPE) and Panavia F (Kuraray), each with an acidic composition, were used in combination with a zirconium oxide (DCS Dental AG) substrate containing Al(2)O(3) and SiO(2) (Rocatec system, 3M ESPE) and two air-particle abrasion methods. The shear bond strength of the resin composite cement to the substrate was tested after the samples were either water-stored for one week or thermocycled following 24 hours of water storage. Results: The RelyX Unicem resin composite cement specimens with the Rocatec treatment (20.9 +/- 4.6 Mpa and 20.1 +/- 4.2 MPa, respectively, n=12) demonstrated the highest shear bond strength. Alternatively, the lowest values were obtained for the Panavia F resin cement samples, with Al(2)O(3) air-particle abrasion in both storage conditions, water storage for one week (17.7 +/- 8.9MPa) or thermocycling after 24 hours of water storage (16.3 +/- 4.9 MPa). Neither storage condition or particle abrasion system significantly affected shear bond strengths (ANOVA, p > 0.05). Conclusion: It was concluded that two different surface conditioning methods and storage conditions did not significantly affect the bonding properties of Panavia F and RelyX Unicem resin composite luting cements to Zirconia.
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    Fabrication of a sectional impression tray and sectional complete denture for a patient with microstomia and trismus: A clinical report
    (Mosby, Inc, 2003) Cura, C; Cotert, HS; User, A
    This article describes techniques used to fabricate mandibular and maxillary sectional trays and a folding maxillary complete denture for a patient with limited oral opening caused by scleroderma. For the foldable denture, the anterior teeth had to be arranged on a second base and the hinge fitted at a location higher than the denture base. These 2 factors increased the thickness of the denture and limited the volume of the tongue. Nevertheless, a single-piece denture base provided the patient with ease in placement and removal of the denture.
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    Fabrication of a sectional impression tray and sectional complete denture for a patient with microstomia and trismus: A clinical report
    (Mosby, Inc, 2003) Cura, C; Cotert, HS; User, A
    This article describes techniques used to fabricate mandibular and maxillary sectional trays and a folding maxillary complete denture for a patient with limited oral opening caused by scleroderma. For the foldable denture, the anterior teeth had to be arranged on a second base and the hinge fitted at a location higher than the denture base. These 2 factors increased the thickness of the denture and limited the volume of the tongue. Nevertheless, a single-piece denture base provided the patient with ease in placement and removal of the denture.
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    Intra-oral adhesive systems for ceramic repairs: a comparison
    (Taylor & Francis Ltd, 2003) Kumbuloglu, O; User, A; Toksavul, S; Vallittu, PK
    The aim of this investigation was to compare the bond strength of restorative composite resin to dental ceramic conditioned with primers and adhesives of various commercial repair kits. Three intra-oral ceramic repair systems-Silistor (Heraeus Kulzer), Cimara (Voco), Ceramic Repair (Vivadent)-were used on all-ceramic (IPS Empress 2, Ivoclar-Vivadent) substrate. Shear bond strength of restorative composite resin to substrate was tested after thermocycling and without thermocycling (n = 10). Substrate surfaces of the specimen after loading were examined microscopically (SEM). The highest bond strengths in both water-stored (7.0 +/- 5.7 MPa) and thermocycled conditions (2.5 +/- 1.8 MPa) were obtained with the Vivadent repair system, while the lowest values were observed with the Cimara system (0.6 +/- 1.4 MPa and 0.0 +/- 0.0 MPa, respectively). Shear bond strengths appeared to be significantly affected by thermocycling (ANOVA, P< 0.05). It is concluded that there are significant differences in the bond strengths of resin composites and ceramic substrate. The roughened surface does not necessarily provide a better bond strength; the bond strength of composite decreases with storage in water and after thermocycling. Bond strength values were generally low for all of the tested materials.
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    Intra-oral adhesive systems for ceramic repairs: a comparison
    (Taylor & Francis Ltd, 2003) Kumbuloglu, O; User, A; Toksavul, S; Vallittu, PK
    The aim of this investigation was to compare the bond strength of restorative composite resin to dental ceramic conditioned with primers and adhesives of various commercial repair kits. Three intra-oral ceramic repair systems-Silistor (Heraeus Kulzer), Cimara (Voco), Ceramic Repair (Vivadent)-were used on all-ceramic (IPS Empress 2, Ivoclar-Vivadent) substrate. Shear bond strength of restorative composite resin to substrate was tested after thermocycling and without thermocycling (n = 10). Substrate surfaces of the specimen after loading were examined microscopically (SEM). The highest bond strengths in both water-stored (7.0 +/- 5.7 MPa) and thermocycled conditions (2.5 +/- 1.8 MPa) were obtained with the Vivadent repair system, while the lowest values were observed with the Cimara system (0.6 +/- 1.4 MPa and 0.0 +/- 0.0 MPa, respectively). Shear bond strengths appeared to be significantly affected by thermocycling (ANOVA, P< 0.05). It is concluded that there are significant differences in the bond strengths of resin composites and ceramic substrate. The roughened surface does not necessarily provide a better bond strength; the bond strength of composite decreases with storage in water and after thermocycling. Bond strength values were generally low for all of the tested materials.
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    A study of the physical and chemical properties of four resin composite luting cements
    (Quintessence Publ Co Inc, 2004) Kumbuloglu, O; Lassila, LVJ; User, A; Vallittu, PK
    Purpose: This study evaluated the surface microhardness and flexural and compressive strengths of five luting cements and compared the degree of conversion of dual and autopolymerized forms of four resin-based luting cements. Materials and Methods: Four resin composite luting cements-Panavia F, Variolink 2, RelyX Unicem Applicap, and RelyX ARC-and a polycarboxylate cement (Durelon, control group) were used in three-point bending, compression, and Vickers hardness tests following water storage for 1 week. Resin composite cements were additionally investigated with both dual and autopolymerization techniques under Fourier transformed infrared spectroscopy. Differences were analyzed using one-way ANOVA. Results: The highest flexural strengths were obtained with Variolink 2 (90 MPa, SD 22), whereas the lowest were observed with Durelon (28 MPa, SD 4). RelyX Unicem showed the highest hardness values (44 HV, SD 5), whereas Variolink 2 gave the lowest (32 HV, SD 6). The highest compressive strengths were obtained with RelyX Unicem (145 MPa, SD 32), whereas the lowest were observed with Durelon (41 MPa, SD 17). For both dual and autopolymerized groups, RelyX ARC showed the highest degrees of conversion (81% and 61%, respectively) and RelyX Unicem had the lowest (56% and 26%, respectively). Conclusion: Resin composite luting cements of similar chemical characterizations differed in their physical properties, and polymerization method influenced their degree of conversion.