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Öğe Bond strength of glass-fiber post to dentine after some treatment methods(2012) Oral O.; Kumbuloglu O.; Lassila L.V.J.; User A.; Vallittu P.K.The purpose of this study was to evaluate the effects of various root canal treatment methods on bonding strength of a glass-fiber post to root canal dentin. 60 human maxillary anterior teeth were prepared with ParaPost (Coltene) up to diameter of 1.75 mm with drills of 1.14, 1.25, 1.40, 1.50 and 1.75 mm from 1 mm coronal level of apices. The upper surfaces of polished areas were ground to acquire correct angle with the long axis of drills and the specimens were divided into 6 groups (n=10). Glass-fiber posts (1.5mm) (everStick POST, StickTech) were cemented with a dual-cure composite resin cement (ParaCem, Coltene) after following treatment methods. (Group 1) 0.9% isotonic NaCl solution (control), (Group 2) 2.5% NaOCl + Er:YAG Laser (Kavo K-E-Y), (Group 3) 2% Chlorhexidine + Er:YAG Laser , (Group 4) Slurry Bioactive Glass Granules (Vivoxid), (Group 5) Silane-based Primer (3M, ESPE, RelyX) + Er:YAG Laser, (Group 6) Slurry Bioactive Glass Granules + Silane-based Primer + Er:YAG Laser. From each root, two disks of 2 mm thickness was obtained. The push-out test was carried out by using a universal testing device (Lloyd LRX) with a loading tip (diameter 1.7 mm, crosshead speed of 1.0 mm/min) until loosening of the post. Statistical analysis was performed using ANOVA followed by post-hoc comparisons (Tukey B, p<0.05). Root canals were evaluated by SEM. Bond strength of fiber posts were significantly affected by the type of treatment (p<0.05). The highest bond strength was observed in Group 5, whereas the lowest bond strength values were recorded with the Group 3. Bond strength of glass-fiber post to root canal dentin was affected by treatment method. Treatment with laser and Bioactive Glass Granules in combination of using silane yielded the highest bond strength. © (2012) Trans Tech Publications.Öğe Bond strength of luting cement to casting and soldering alloy.(2006) Kumbuloglu O.; Lassila L.V.; User A.; Toksavul S.; Vallittu P.K.Adjustment of metal alloy framework of the porcelain-fused-to-metal crown by soldering minor marginal deficiences prior insertion may sometimes be needed. The aim of this study was to compare shear bond strengths of four luting cements to casting metal alloy and soldering metal alloy. A total of 64 flame cast non-precious metal alloy and flame soldered metal alloy samples were used. Durelon, Panavia F, RelyX Unicem Applicap and RelyX ARC stubs were bonded to the alloy substrate surface. After stored in water at 37 degrees C for 1 week, shear bond strength of the cement to the alloy was measured. Differences were analyzed using one way ANOVA (p<0.05). There were no difference between the cast metal alloy and soldering metal alloy substrate.Öğe Bonded orthodontic retainer and fixed partial denture made with fiber reinforced composite resin(2011) Kumbuloglu O.; Saracoglu A.; Cura C.; User A.Retention is the phase of orthodontic treatment which maintains teeth in their orthodontically corrected positions, following the cessation of active orthodontic tooth movement. Development of resin-impregnated, fiber-reinforced composite materials has provided the potential to develop new approaches for stabilizing teeth and replacing teeth conservatively. This case report describes the rehabilitation of a patient with orthodontic and prosthetic problems. The long-term behavior of glass fibers splint must be evaluated in clinical studies.Öğe Clinical evaluation of different gingival retraction cords(2007) Kumbuloglu O.; User A.; Toksavul S.; Boyacioglu H.Objectives: Impression techniques in restorative dentistry require displacement of gingival tissues to expose subgingival finish lines on tooth preparations. Retraction cords are commonly used for this purpose. Some cord systems include various medicaments, which may remain in the sulcus after retraction procedures. The purpose of this study was to determine whether any of the commonly used gingival retraction medicaments could influence the surface characteristics of the impression material and to evaluate the clinical performance of retraction cords. Method and Materials: Sixteen cord systems in various shapes, sizes, and medications were used in this study. The clinical performances of cords were evaluated with a blind experimental study design, according to predetermined criteria. Results were analyzed by using chi-square test and ordinal logistic regression analysis (P < .05). Results: Statistically significant differences were found in all criteria among groups (P < .05). None of the materials investigated appeared to have any influence on the surface characterization of the polyvinyl siloxane impression material used. Better impression qualities were observed in groups with easy insertion, proper dilatation, less recurrent bleeding, and no remnants or fraying. Logistic regression analysis revealed that both retraction cord medicaments (odds ratio = 0.63, P = .00 < .05) and cord thicknesses (odds ratio = 2.09, P = .00 < .05) were important risk factors on the gingival margin quality. Conclusions: The applied gingival retraction cord systems had no influence on the surface characterization of the polyvinyl siloxane material tested. Gingival margin quality of the impression and clinical application procedures were affected by the retraction systems. Untreated, medium-braided, and epinephrine-impregnated cord systems were clinically successful. However, the potential systemic effects of epinephrine must be considered. © 2007 by Quintessence Publishing Co Inc.Öğe Effects of non-silanized and silanized glass particles on the physical properties on denture base materials(2012) Oral O.; Lassila L.V.J.; Kumbuloglu O.; User A.; Vallittu P.K.The purpose of this study was to evaluate the effects of silanization of the glass on denture base materials and to evaluate different types of glasses. A total of 136 Poly(methyl methacrylate) (PMMA) (Palapress - Heraeus Kulzer) blocks were prepared in dimensions of 65mm × 10mm × 3mm. PMMA blocks were modified by different ratios of non-silanized and silanized Bioactive Glass Granules (BAG) (Vivoxid) and Inert Glass Granules (IG) (Vivoxid). The blocks were polished under water cooling and divided into 17 groups. (Group 1) No glass (control), (Group 2-5) 3-6-9-12% non-silanized BAG, (Group 6-9) 3-6-9-12% silanized BAG, (Group 10-13) 3-6-9-12% non-silanized IG, (Group 14-17) 3-6-9-12% silanized IG. The specimens were stored in distilled water and weighed (Mettler, Toledo) in days of 1, 2, 3, 7, 14, 21, 30, 45, 60. After water sorption test, the specimens were dried under 80°C and weighed in days of 0, 1, 2, 3, 5, 7, 9 for calculating the solubility values. Statistical analysis was performed using analysis of variance (ANOVA) followed by post-hoc comparisons (Dunnett T3, p<0.05). Water sorption and solubility values were significantly affected by the type and silanizaion of the glass (p<0.05). The highest water sorption value was observed in 12% silanized IG group (1,83±0,04%), whereas the lowest sorption values were recorded with 12% non-silanized BAG group (1,21±0,07%). Contrarily, The highest solubility value was observed in 12% non-silanized BAG group (0,98±0,03%), whereas the lowest solubility values were recorded with 12% non-silanized BAG group (0,34±0,03%). Water sorption and solubility values were affected by the type and silanization of the glass. Silanization improved the physical properties of the glass as well as the properties of the denture base material. © (2012) Trans Tech Publications.Öğe Fracture strength of fiber-reinforced surface-retained anterior cantilever restorations(2008) Özcan M.; Kumbuloglu O.; User A.Purpose: This study compared the fracture strength of direct anterior cantilever fiber-reinforced composite (FRC) fixed partial dentures (FPD) reinforced with 3 types of E-glass fibers preimpregnated with either urethane tetramethacrylate, bisphenol glycidylmethacrylate/polymethyl methacrylate, or bisphenol glycidylmethacrylate monomers and 1 ultrahigh molecular weight polyethylene fiber. Failure types were also evaluated. Materials and Methods: A total of 40 caries-free, human maxillary central incisors (n = 10 per group) received surface-retained direct cantilever restoration (1 pontic) after etching and application of bonding agent. Four FRC materials were used (FRC1 = EverStick; FRC2 = BR-100; FRC3 = Interling; FRC4 = Ribbond), and pontics were built up using 1 particulate filler composite (Clearfil Photo Posterior). After the fracture test, failure types were analyzed. Results: No significant difference was found between the 4 FRC types veneered with particulate filler composite (893 ± 459 N to 1326 ± 391 N) (P = .1278). Complete pontic fracture at the connector area was most prominent for FRC4 (90%), followed by FRC3 (70%). Only FRC2 (10%) showed some fiber fractures, with half of the fiber remaining attached on the enamel surface of the abutment. Conclusion: The fracture strengths of cantilever FPDs made of 4 FRC materials with different monomer matrices and architectures, veneered with particulate filler composite, did not show significant differences. However, failure behavior varied between groups.Öğe Shear bond strength of composite resin cements to lithium disilicate ceramics(2005) Kumbuloglu O.; Lassila L.V.J.; User A.; Toksavul S.; Vallittu P.K.The aim of this study was to evaluate the shear bond strength of different commercial composite resin cement systems to lithium disilicate allceramic substrate. Five adhesive resin cement systems Panavia 21 and Panavia F (Kuraray), Variolink 2 (Ivoclar-Vivadent), RelyX Unicem Applicap and RelyX ARC (3M ESPE) were used on all-ceramic (IPS Empress 2; Ivoclar-Vivadent) substrate. Shear bond strength of adhesive resin cement to substrate was tested after thermocycling, or without thermocycling (n = 10). Substrate surfaces of the specimen after loading were SEM microscopically examined. The highest bond strengths in water stored conditions were obtained with RelyX ARC (28-7 ± 3.9 MPa), while in thermocycled conditions the highest bonding values were obtained with Variolink 2 (23.2 ± 7.5 MPa). The lowest values in both water stored (5.8 ± 4.0 MPa) and thermocycled (2.4 ± 2.9 MPa) conditions were obtained with Panavia 21. Shear bond strengths appeared to be affected significantly by thermocycling (ANOVA, P < 0.05). It was concluded that there were significant differences between the bond strengths of adhesive resin cements to lithium disilicate substrate.
