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Öğe Adhesion of resin composite to hydrofluoric acid-exposed enamel and dentin in repair protocols(2011) Saracoglu A.; Özcan M.; Kumbuloglu O.; Turkun M.Intraoral repairs of ceramic fixed-dental-prostheses (FDP) often include cervical recessions that require pretreatment of the exposed tooth surfaces either before or after the ceramic is conditioned with hydrofluoric (HF) acid gel. The sequence of repair protocol may crosscontaminate the exposed etched enamel or dentin surfaces during the application or rinsing process and thereby affect the adhesion. This study evaluated the influence of HF acid gel with two concentrations on bond strengths of composite to enamel and dentin. Human third molars (N=100, n=10 per group) with similar sizes were selected and randomly divided into 10 groups. Flat surfaces of enamel and dentin were created by wet ground finishing. Before or after the enamel (E) or dentin (D) was conditioned with phosphoric acid (P), substrate surfaces were conditioned with either 9.5% HF (HF9.5) or 5% HF (HF5). Subsequently, a bonding agent (B) was applied. The experimental groups by conditioning sequence were as follows where the first letter of the group abbreviation represents the substrate (E or D) followed by the acid type and concentration: group 1 (EPHF 9.5), group 2 (EPHF 5), group 3 (EHF 9.5P), group 4 (EHF 5P), group 5 (DPHF 9.5), group ± (DPHF 5), group 7 (DHF 9.5P), and group 8 (DHF 5P). Group 9 (EPB) and group 10 (DPB) acted as the control groups. Repair resin was adhered incrementally onto the conditioned enamel and dentin in polyethyl-ene molds. Each layer was photo-polymerized for 40 seconds. All specimens were thermocycled (×1000, 5°-55°C) and subjected to shear test (universal testing machine, 1 mm/min). Specimens that debonded during thermocycling were considered as 0 MPa. The bond strength data were analyzed using Kruskal-Wallis test and failure types using the chi-square test (?=0.05). Overall, the bond results (MPa) were lower on dentin than on enamel (p<0.01). EPB (25.6 ± 6.6) and DPB (20.2 ± 4.9) control groups showed significantly higher results than those of other groups (p<0.05). While higher mean bond strengths were obtained in group 1 (EPHF9.5) (11.5 ± 2.1) and group 2 (EPHF5) (7.3 ± 0.6), lower results were obtained when HF acid gels were applied prior to phosphoric acid (EHF 9.5P: 5.0 ± 1.1, EHF5P: 3.6 ± 0.1) (p<0.05). On dentin, the results were the lowest in group 8 (DHF5P: 1.5 ± 1.6), being significantly lower than those of group 5 (DPHF 9.5) (p<0.05). Scanning electron microscope (SEM) images revealed predominantly mixed failures with less than half of the composite left on both enamel and dentin surfaces (64 out of 80) (p<0.05), indicating that in general, adhesion was not ideal. Contamination of the enamel or dentin surfaces with HF acid gel impairs the bond strength of composites. Considering both the bond strength results and failure types, when dental tissues are to be repaired next to ceramic, application of phosphoric acid before HF acid gel application can be recommended. HF acid gel concentration did not influence the results except on enamel. © Operative Dentistry, 2011.Öğe Anatomical and radiological investigation of dry bone adult mandibles having impacted third molar teeth(Lippincott Williams and Wilkins, 2018) Cirpan S.; Kumbuloglu O.; Yonguc G.N.; Sayhan S.; Bulut B.; Güvençer M.Objective: To investigate the incidence of the impacted mandibular third molars in dry bones adult mandibles. Methods: The 198 dry bones adult mandibles gathered from the bone collections in Laboratory of the Anatomy Department of Dokuz Eylul University School of Medicine were macroscopically examined for the presence of impacted mandibular third molars. The genders of the adult bones were unknown. The adult mandibles having impacted third molars were photographed with Canon 400B (55 mm objective). The mandibles having impacted third molars were also radiographically examined with orthopantomography (a dental radiographic technique, kV 60, mA 2.0) in radiology unit of Faculty of Dentistry, Ege University. The impacted teeth were grouped according to their position and degree of impaction. Results: The each of 2 of 198 adult mandibles (2/198; 1.01%) was having an impacted 3rd molar teeth. These 2 molar teeth were belonged to class 1, B and partially buried, vertically oriented. The first impacted 3rd molar teeth was located on the left side of the one mandible and the second one on the right side of the other mandible. Conclusion: The present study provides information about impacted mandibular 3rd molar in dry bones. © 2018 by Mutaz B. Habal, MD.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 Candida albicans adherence on silicone elastomers: Effect of polymerisation duration and exposure to simulated saliva and nasal secretion(2010) Kurtulmus H.; Kumbuloglu O.; Özcan M.; Ozdemir G.; Vural C.Objectives: The surfaces of maxillo-facial prostheses made of silicone elastomers exposed to soft tissues may interact with saliva and nasal secretion. These body fluids may lead to colonisation of microorganisms on their surfaces leading to their degradation or infection. This study investigated Candida albicans adhesion onto commercial maxillo-facial silicone elastomers based on different polymerisation processes. Methods: Room-temperature polymerised maxillo-facial silicone elastomers (N = 48) (10 mm × 10 mm × 2 mm) processed at different durations [VerSilTal VST-30 (20 min), VST-50 (12 h overnight), VST-50F (6 h)] were studied. C. albicans was chosen as a model organism for this study. The specimens were randomly divided into two subgroups and incubated in either 1.5 ml simulated saliva or nasal secretion containing C. albicans (ATCC 60193, set to 0.5 OD, 540 nm in advance) for 2 h. Candida assays and adherence assays were made by inoculating C. albicans into Mueller Hinton Broth, Fluka® added 500 mmol sucrose overnight. After fixation, specimens were stained by using sterilised Methylene Blue stain (Merck®) and evaluated under optical microscope and SEM. For each material, on each specimen 15 different areas (mm2) were counted. Data were analysed using one-way ANOVA, paired sample t-test and Tukey's HSD (? = 0.05). Results: Material type (p < 0.05) and exposure media (p < 0.05) showed a significant influence on the C. albicans adherence. VST-30 material showed the most C. albicans adherence in both saliva and nasal secretion (mean rank: 99.84 and 53.47, respectively) (p < 0.05) and VST-50 had the least colonisation in both media (10.35 and 5.57, respectively). Microscopic evaluation showed clusters of blastospore cells of C. albicans being more spread out on VST-30 whereas cells were more localised on VST-50 and VST-50F. Significance: Among the tested materials, 12 h room-temperature polymerised silicone elastomer resulted in less C. albicans adherence in both artificial saliva and nasal secretion. © 2009 Academy of Dental Materials.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 Effect of various disinfection methods on bonding strength of glassfibre post to root canal dentine(2012) Kumbuloglu O.; Lassila L.V.J.; Turkun M.; Vallittu P.K.Disinfection is a critical step in the treatment of a root canal before sealing it with post. This study was to evaluate the effects of various root canal disinfection methods on the bond strength of a glassfibre post to root canal dentine. Forty-eight premolars were studied. The root canals were divided into six groups. Glassfibre posts were cemented with a dual cure composite resin cement following disinfection by using Waterlase laser, Key laser, bioactive glass granules, Tubulicid Plus, NaCl solution (control) and NaOCl solution. Specimens were stored for 8 months. The root part of the tooth was cut and prepared into an hourglass shaped specimen for microtensile bond test. Statistical analysis was performed. Failure types were evaluated and SEM images were taken. The bond strength of fibre posts was significantly affected by the type of disinfection. The highest microtensile bond strength was observed in specimens disinfected by using bioactive glass granules, whereas the lowest bond strength values were recorded with NaOCl irrigation. The bond strength of glassfibre post to root canal dentine was affected by disinfection procedure. © 2012 W. S. Maney & Son Ltd.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.
