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Öğe Colour Stability of Three Esthetic Laminate Materials Against to Different Staining Agents(1997) Belli, S.; Tanrıverdi, F. F.; Belli, E.The purpose of the present study was to evaluate the colour stability of three laminate veneer materials against to tea, coffee and cigarette smoke. 72 discs prepared by using two different type composite materials and a dental porcelain were divided into groups and immersed into distilled water, tea, Turkish coffee solutions. The last group was exposed to cigarette smoke. Colour differences were measured by colorimeter at the beginning and then in the period of 1 day, 1 week and 1 month respectively. As a result, it was found that cigarette smoke was the most staining agent, porcelain material was the most colour stable material, and indirect composite material was more colour stable than the direct one.Öğe Comparison of Two Different Post and Core Systems Using a Finite Element Stress Analysis and a Conventional Fracture Strength Test(INT AMER ASSOC DENTAL RESEARCHI A D R/A A D R, 2001) Eskitasçıoğlu, G.; Belli, S.; Kalkan, M.[Abstract not Available]Öğe Effect of Cavity Varnish, Amalgam Liner or Dentin Bonding Agents on the Marginal Leakage of Amalgam Restorations(BLACKWELL SCIENCE LTD, 2001) Belli, S.; Ünlü, N.; Özer, F.The purpose of this in vitro study was to compare marginal leakage of Class II amalgam restorations lined with different agents (two new generation dentin bonding systems, a cavity varnish and an amalgam liner). Forty freshly extracted human molar teeth were divided into five groups. Class II preparations were prepared in the mesial and distal surfaces of each molar. While the cavities in two groups were lined with two new generation bonding systems, the other two groups were treated with an amalgam lining material and a cavity varnish. Fifth group was used as control, without any lining. Amalgam was hand-condensed into each preparation. Specimens were thermocycled, stained and sectioned. Microleakage was graded using a stereomicroscope. Mean microleakage scores for occlusal and cervical margins were calculated and analised. For the leakage values on occlusal margins, Kruskal-Wallis test indicated no significant difference in all groups. For the leakage values on cervical margins, Kruskal-Wallis test indicated significant difference in four groups when compared with controls (P < 0.001). On the other hand, there was no significant difference between the occlusal and cervical leakage values in each group.Öğe The Effect of Different Posts on Fracture Strength of Roots with Vertical Fracture and Re-Attached Fragments(WILEY-BLACKWELL, 2010) Özçopur, Betül; Akman, Serhan; Eskitasçıoğlu, Gürcan; Belli, S.P>The aim of this in vitro study was to test the effect of different post systems on fracture strength of roots with re-attached fragments. Root canals of eighty extracted single-rooted human teeth were instrumented (ProFile) and randomly divided into two groups. The roots in the first group were vertically cracked, and the fragments were re-attached using Super Bond C&B (Sun Medical, Tokya, Japan). The roots in the second group were kept sound. Obturation of the roots was performed with MetaSEAL (Sun Medical) and gutta-percha. Post spaces were prepared, and the roots were restored with one of the followings: UniCore (Ultradent), Everstick (Stick Tech), Ribbond (Ribbond), ParaPost (Coltene/Whaledent) (n = 10). Four mm high build-ups were created (Clearfil DC Bond Core; Kuraray, Tokyo, Japan). Compressive loading of the samples was performed after 24 h (1 mm min-1). Mean load necessary to fracture each sample was recorded (Newton) and statistically analysed (One-way anova, t-tests). ParaPost showed the highest fracture strength among the roots with re-attached fragments (P < 0.05). UniCore and ParaPost systems showed similar fracture strength in the sound roots (P > 0.05). Re-attached fragments significantly reduced the fracture strength of roots in UniCore group (P = 0.000). Ribbond post showed mostly repairable fractures. Metal post (ParaPost) showed the highest fracture strength in the roots with re-attached fragments; however, fracture pattern was 41% non-repairable. Re-attached fragments significantly reduced the fracture strength of the roots in UniCore group. Prefabricated posts showed similar fracture strength in the sound roots. Customized post systems EverStick and Ribbond showed mostly repairable failure after loading in sound roots or roots with re-attached fragments.Öğe Effect of surface treatments and different adhesives on the hybrid layer thickness of non-carious cervical lesions(OPERATIVE DENTISTRY INC, 2008) Eliguzeloglu, E.; Omurlu, H.; Eskitascioglu, G.; Belli, S.This in vitro study observed and compared the resin and non-carious sclerotic dentin interfaces generated by three different adhesives and two different techniques, using a scanning electron microscope (SEM). Thirty-two human premolars, with buccal, non-carious cervical lesions, were used. The teeth were randomly divided into eight groups. Group 1: Sclerotic dentin was treated with Single Bond (3M). Group 2: After superficial sclerotic dentin was removed with a diamond bur (Diatech, Coltene), the dentin surfaces were treated with Single Bond. Group 3: Sclerotic dentin was treated with Clearfil SE Bond (Kuraray). Group 4: After superficial sclerotic dentin was removed with a diamond bur, Clearfil SE Bond was applied. Group 5: Sclerotic dentin was treated with Xeno III (Dentsply). Group 6: After superficial sclerotic dentin was removed with a bur, Xeno III was applied to the dentin surfaces. For Groups 7 and 8, after the superficial sclerotic dentin was removed with a diamond bur, Clearfil SE Bond, with an additional 37% phosphoric acid gel, was used on the sclerotic dentin surfaces in Group 7 and Xeno III was used in Group S. In all groups, the cavities were restored with Filtek Supreme (3M). All the specimens were sectioned longitudinally and polished along the cut surface. The sections were treated with 37% orthophosphoric acid for five seconds, rinsed with water and treated with 5% NaOCL for 10 minutes. The specimens were then gold-sputter coated and evaluated under SEM. The thickness of the hybrid layer was measured on the gingival, occlusal and axial dentin interfaces. ANOVA was performed to determine whether there were any statistically significant differences in hybrid layer thickness. Post-hoc multiple comparisons were done with Tukey's test. Hybrid layer thickness was increased with all adhesives when superficial dentin was removed with a bur. Hybrid layer thickness showed significant differences between total-etch and self-etch systems.Öğe Effects of NaOCl, EDTA and MTAD when applied to dentine on stress distribution in post-restored roots with flared canals(WILEY, 2014) Belli, S.; Eraslan, O.; Eraslan, O.; Eskitascioglu, M.; Eskitascioglu, G.AimTo evaluate the effect of NaOCl, EDTA and MTAD on the stress distribution and levels in roots with flared canals and three different aesthetic post systems using finite element stress analysis (FEA). MethodologyThree-dimensional (3D) FEA models simulating a maxillary incisor with excessive structural loss and flared root canals were created. The dentine of the first models of each post group was assumed as homogenous, whereas the others were deemed as having their elastic modulus affected up to 100m deep as a result of irrigation protocol (5.25 NaOCl, 17% EDTA and MTAD for 2h). A sound incisor tooth model was used as the control. Restorations were created according to the post system used (pre-fabricated fibre post (PFP)), polyethylene fibre (Ribbond) post and core build-up (RBP), and one-piece milled zirconia post and core (ZP). Ceramic crowns were added to the models. A 300-N static load was applied at the centre of the palatal surface of the models to calculate the stress distributions. The SolidWorks/Cosmosworks structural analysis programmes were used for FEA analysis. Results were presented by considering von Mises criteria. ResultsThe analysis of the von Mises stresses revealed that RBP created less stress in the remaining root dentine when compared to PFP and ZP. ZP maintained the stresses inside its body and reduced stress on the palatal surface of the root; however, it forwarded more stress towards the apical area. NaOCl-, EDTA- and MTAD-treated dentine increased the stresses within the root structure regardless of the effect of the post system used (11-15.4 MPa for PFP, 9.5-13.02 MPa for RBP and 14.2 MPa for ZP). Amongst the irrigation solutions used, EDTA and MTAD increased the stresses more than NaOCl in all models. All the irrigation solutions showed the same stress levels and distributions in the ZP model. ConclusionNaOCl-, EDTA- and MTAD- treated dentine and a rigid post with high elastic modulus may increase fracture risk in roots with flared canals by increasing the stresses within root dentine. Therefore, solutions that alter the elastic modulus of dentine less (such as NaOCl) or an individually shaped post-core system constructed with a material that has an elastic modulus close to dentine (polyethylene fibre) should be used in weak roots.Öğe Evaluation of the sealing ability of gutta-percha and thermoplastic synthetic polymer-based systems along the root canals through the glucose penetration model(MOSBY-ELSEVIER, 2007) Kaya, B. Ureyen; Kececi, Ayse Diljin; Belli, S.Objective. To compare the sealing ability of gutta-percha and thermoplastic synthetic polymer-based systems along the root canals using a recently introduced glucose penetration model. Study design. Premolars (n = 156) instrumented to an apical size of .06/40 were divided into 12 experimental and 2 control groups. The root canals were filled with either gutta-percha (groups 1-6) or Resilon (groups 7-12) core materials combined with AH Plus (groups 1, 4, 7, 0), Ketac Endo (groups 1, 5, 8, 11), or Epiphany (groups 2, 6, 9, 12), using cold lateral compaction (groups 1-3, 7-9) or System B with Obtura 11 (groups 4-6, 10-12). The leaked glucose concentration was measured spectrophotometrically at 1, 8, 15, 22, and 30 days. Percentage leaking of each group was also Calculated. Data were recorded as mmol/L and statistically analyzed with Kruskal-Wallis and Mann-Whitney U tests (11 = 05). Results. Throughout the experimental period Resilon/Ketac-Endo/cold lateral compaction (group 8) showed the highest mean cumulative glucose penetration (mmol/L) (17.27 +/- 10.32), whereas Resilon/AH Plus/cold lateral compaction (group 7) had the least (3.36 +/- 4.65) (P < .05). At the 30(th) day, the least leaking percentage was observed in gutta-percha, Epiphany/cold lateral compaction (group 3). Glucose penetration was affected by the obturation technique in some groups. Ketac-Endo either with gutta-percha (group 2) or Resilon (group 8) indicated significantly less glucose penetration in warm technique, whereas gutta-percha/Epiphany (group 3) had significantly less glucose penetration in cold technique (P < .05). Conclusions. All material/technique combinations allowed glucose penetration. Gutta-percha/AH Plus combinations allowed similar patterns Of glucose penetration to Resilon/Epiphany combinations.Öğe Impact of conditioning regimens and time on adhesion of a fiber post to root dentin using two resin cements(TAYLOR & FRANCIS LTD, 2015) Neelakantan, P.; Mohanraj, R.; Chua, E.; Belli, S.The aim of this study was to evaluate the influence of irrigation protocols on the bond strength of a glass fiber post bonded to dentin using two resin cements. In 200 root-filled teeth, post space was prepared and divided into five groups (n = 40) based on the irrigation protocol: group 1 (3% sodium hypochlorite), group 2 (3% sodium hypochlorite - 17% Ethylene diamine tetraacetic acid), group 3 (a mixture of sodium hypochlorite and etidronic acid), group 4 (sodium hypochlorite - QMix), and group 5 (distilled water). Samples were subdivided into two subgroups (n = 10) and fiber posts were cemented using subgroup A (Self-adhesive dual-cure resin cement; SEA) or B (dual-cure resin cement following an etch-and-rinse protocol, ER). Push-out bond strength was performed after 24h and four months (n = 10) and failure modes were categorized. Statistical analysis of data was carried out by appropriate analyses (p<0.05). The irrigation protocol and the resin cement had a significant impact on push-out bond strength. Subgroup A group showed lower bond strength than B at both time periods when 3% NaOCl-17% EDTA and 1:1 mixture of 6% NaOCl+18%EA protocols were used. Three percent NaOCl used in combination with 17% EDTA or QMix significantly decreased the push-out bond strength of ER at the end of four months (p<0.05). In conclusion, dual-cure resin cements bonded with etch-and-rinse protocol showed highest bond strength when a mixture of NaOCl and etidronic acid was used as root canal irrigant. These values were differentially influenced by time.Öğe An in Vitro Test Model for Investigation of Disinfection of Dentinal Tubules Infected with Enterococcus Faecalis(1997) Tanrıverdi, F.; Esener, T.; Erganiş, O.; Belli, S.The aim of the present study was to develop an in vitro test model from human teeth to comparatively examine antibacterial effectiveness of calcium hydroxide, parachlorophenol (PCP) and camphorated parachlorophenol (CPCP) against Enterococcus faecalis in infected root canals. Cylindrical dentin specimens were prepared from freshly extracted human maxillary anterior teeth. The specimens were inoculated with E. faecalis and then medicated with either CPCP, PCP or Ca(OH)2. The disinfecting efficacy of these agents was tested by collecting dentin chips from the inner ("canal") walls of the specimens and counting viable E. faecalis. The dentin chips were diluted and a classical bacterial count technique was used for recovery of E. faecalis strains of 5% sheep blood agar. The effectiveness of CPCP and PCP at one day was superior to the effectiveness of Ca(OH)2. In the three-day group, CPCP was the most effective, followed by Ca(OH)2. The experimental model used in this study may be useful for investigation of the effect of intracanal medicaments on microorganisms lodged in the root dentinal tubules.Öğe The influence of irrigating solutions on the accuracy of the electronic apex locator facility in the Tri Auto ZX handpiece(BLACKWELL PUBLISHING, 2007) Erdemir, A.; Eldeniz, A. U.; Ari, H.; Belli, S.; Esener, T.Aim To determine the influence of various irrigating solutions on the accuracy of the electronic apex locator facility in the Tri Auto ZX handpiece. Methodology One hundred and forty teeth with single canals and mature apices, scheduled for extraction for either periodontal or prosthetic reasons in 76 patients were used. Following informed written consent local anaesthesia was administered, access cavities were prepared and pulp tissue removed. The teeth were then randomly divided into seven groups according to the irrigating solutions used. The root canal length measurements were completed using the Tri Auto ZX handpiece with automatic reverse function in the presence of one or other of the following solutions: 0.9% saline, 2.5% NaOCl, 3% H2O2, 0.2% chlorhexidine, 17% EDTA, Ultracaine((R)) D-S or in the absence of an irrigating solution (control). Files were immobilized in the access cavity with composite resin. After extraction, the apical regions of the teeth were exposed and the file tips examined under a stereomicroscope. Distances between the file tips and the apical constriction were measured (mm) and analysed using a one-way ANOVA and post hoc Tukey test. Results Mean distances from the apical constriction to the file tip were longer in the 0.9% saline group (P < 0.05). There was no statistically significant difference on file tip position between the other solutions. Conclusions Tri Auto ZX gave reliable results with all irrigating solutions apart from in the presence of 0.9% saline.Öğe Micropush-out bond strengths of gutta-percha versus thermoplastic synthetic polymer-based systems - an ex vivo study(WILEY, 2008) Kaya, B. Uereyen; Kececi, A. D.; Orhan, H.; Belli, S.Aim To compare the interfacial strength and failure mode of root fillings consisting of different technique-material combinations. Methodology Human mandibular premolars (n = 144) instrumented to apical size 40 and .06 taper were divided into 12 experimental groups. The root canals were filled with either gutta-percha (groups 1-6) or Resilon (groups 7-12) core materials combined with AH Plus (groups 1, 4, 7, 10), Ketac-Endo (groups 2, 5, 8, 11) or Epiphany (groups 3, 6, 9, 12) using cold lateral compaction (groups 1-3, groups 7-9) or System B with Obtura II (groups 4-6, groups 10-12). Three serial 1.00 +/- 0.05-mm-thick root slices were prepared and push-out tests on the filling material were performed. Interactions amongst the compaction techniques, core materials and sealers were analysed using a three-way analysis of variance (ANOVA) (P < 0.05). One-way ANOVA and Duncan's Multiple Range tests were used to compare the bond strengths of the 12 groups. Fracture modes of all root slices were evaluated stereomicroscopically at x40 magnification. Results All the parameters except compaction techniques had significant interactions (P < 0.05). A significant difference was found amongst the groups (P < 0.05). Gutta-percha/Ketac-Endo/cold lateral compaction and gutta-percha/AH Plus/cold lateral compaction groups had the highest micropush-out bond strength values (P < 0.05). The number of overall cohesive failures was significantly more than that of adhesive failures (P < 0.05). Conclusions The push-out bond strengths of Resilon/Epiphany combinations were lower than those of gutta-percha/conventional root canal sealer combinations. Core materials and sealers may affect the push-out bond strengths of root canal filling materials.Öğe Monoblocks in root canals: a finite elemental stress analysis study(WILEY-BLACKWELL, 2011) Belli, S.; Eraslan, O.; Eskitascioglu, G.; Karbhari, V.Belli S, Eraslan O, Eskitascioglu G, Karbhari V. Monoblocks in root canals: a finite elemental stress analysis study. International Endodontic Journal, 44, 817-826, 2011. Aim To investigate using finite element stress analysis (FEA) primary, secondary and tertiary monoblocks created either by adhesive resin sealers or by different adhesive posts and to evaluate the effect of interfaces on stress distribution in incisor models. Methodology Seven maxillary incisor FEA models representing different monoblocks using several materials were created as follows: (a) primary monoblock with Mineral Trioxide Aggregate; (b) secondary monoblock with sealer (MetaSEAL) and Resilon; (c) tertiary monoblock with EndoREZ; (d) primary monoblock with polyethylene fibre post-core (Ribbond); (e) secondary monoblock with glass-fibre post and resin cement; (f) tertiary monoblock with bondable glass-fibre post; (g) tertiary monoblock with silane-coated ceramic post. A 300 N load was applied from the palatal surface of the crown with a 135 degrees angle to the tooth long axis. Materials used in the study were assumed to be homogenous and isotropic except the glass-fibre post; the results are expressed in terms of von Mises criteria. Results Maximum stresses were concentrated on force application areas (18-22.1 MPa). The stresses within the models increased with the number of interfaces both for the monoblocks created by the sealers (1.67-8.33 MPa) and for the monoblocks created by post-core systems (1.67-11.7 MPa). Conclusions Stresses within roots increased with an increase in the number of the adhesive interfaces. Creation of a primary monoblock within the root canal either by an endodontic sealer or with an adhesive post-core system can reduce the stresses that occur inside the tooth structure.Öğe No Adverse Effect to Bonding Following Caries Disinfection With Chlorhexidine(2009) Ersin, N. K.; Candan, U.; Aykut, A.; Eronat, C.; Belli, S.Purpose: The purpose of this study was to evaluate the effect of 2% chlorhexidine-based cavity disinfectant on the microtensile bond strength of 3 restorative materials to caries-affected and sound primary dentin. Methods: Eighteen exfoliated primary molars with occlusal caries and 18 sound primary molars were randomly divided into 3 experimental groups, according to the following restorative materials: (1) high-viscosity glass-ionomer cement (GIC; KetacMolar); (2) resin-modified GIC (Vitremer); and (3) dentin adhesive (Prime&Bond NT) with a packable composite (Surefil). The molars were further divided into 2 subgroups according to the application of chlorhexidine-based cavity disinfectant (Consepsis). Standard restoration blocks of 5 mm high were built up over the treated surfaces. Bond strength results were evaluated using by 1-way analysis of variance, and multiple comparisons were done via Tukey's test (P<.05). Results: No statistically significant differences were found between the high-viscosity and resin-modified GIC and composite showed the highest bond strength values on both dentin surfaces. The distribution of failure modes between the high-viscosity and resin-modified GICs were mostly cohesive where adhesive failures were noted significantly in the composite. Conclusion: Using 2% chlorhexidine gluconate did not interfere with the microtensile bond strength of glass ionomer cements and composite.Öğe Periodontal Ligament Fibroblast Response to Root Perforations Restored with Different Materials - A Laboratory Study(WILEY-BLACKWELL, 2012) Hakkı, S. S.; Bozkurt, S. B.; Özcopur, B.; Puralı, N.; Belli, S.Aim To compare the effect of several materials on the attachment of periodontal ligament (PDL) fibroblasts to experimentally perforated root surfaces. Methodology Root specimens (size 5 x 5 mm) were obtained from extracted human molar teeth and perforations with a 1 mm diameter were created. One group was kept as a control and the rest were repaired with the following materials: Amalgam, Dyract, IRM, Super Bond C&B and Mineral trioxide aggregate (MTA). PDL fibroblasts were placed at a density of 8 x 104 cells on the root specimens, incubated on tissue culture inserts (48 h) and then transferred to 48 well-plates. MTT assays were performed at 48 and 96 h for PDL fibroblast survival. Cell attachment was observed using confocal microscopy on days 2 and 5. Total RNAs from the root specimens were isolated on day 5 and type I collagen (COL I) and Runt-related transcription factor 2 (Runx2) mRNA expressions were checked using Quantitative-Polymerase Chain Reaction (QPCR). For the MTT assay and QPCR, one-way analysis of variance (anova) and Tukey HSD multiple comparison tests were used to compare the groups. Results Mineral trioxide aggregate resulted in a significantly higher cell density (P < 0.001). Dyract, IRM and Super Bond C&B groups had a lower cell density when compared with the control and MTA groups at 48 h (P < 0.001). Confocal microscopy revealed that, among the experimental groups, the MTA group had the largest viable cell population over the restoration site when compared with the other materials; however, reduced cell attachment was noted in all groups when compared with the control. Increased Runx2 mRNA expressions were noted in MTA (P < 0.001) and IRM (P < 0.01) groups when compared with control and other tested materials. COL I transcripts were increased in IRM (P < 0.01), D, C&B and MTA (P < 0.001) when compared with the control. Conclusion Mineral trioxide aggregate provided a more favorable environment for PDL cell adhesion and growth.Öğe The response of cementoblasts to calcium phosphate resin-based and calcium silicate-based commercial sealers(WILEY-BLACKWELL, 2013) Hakki, S. S.; Bozkurt, B. S.; Ozcopur, B.; Gandolfi, M. G.; Prati, C.; Belli, S.Hakki SS, Bozkurt BS, Ozcopur B, Gandolfi MG, Prati C, Belli S. The response of cementoblasts to calcium phosphate resin-based and calcium silicate-based commercial sealers. International Endodontic Journal, 46, 242-252, 2013. Aim To investigate cell viability and gene expression of cementoblasts (OCCM.30) exposed to extractable components released by resin-based sealers with different chemical composition Hybrid Root Seal (HRS), SimpliSeal (SS), Real Seal (RS) and AH Plus (AH) and by a MTA-based sealers Tech Biosealer Endo (TBE). Methodology Discs of all materials were prepared and allowed to set in humid conditions at 37 degrees for 48h. The discs were then incubated for 72h at 37 degrees C to obtain material extracts (1/1) in DMEM. The extracts containing the components released by the sealers were filtered and other dilutions (1/2, 1/4) were prepared from the original solution (1/1). Original and diluted solutions were tested on the cementoblasts. Impedance-based real-time cell analysis (RTCA) was used to evaluate cell viability, quantitative real-time polymerase chain reaction (QRT-PCR) was used to examine the expression of mineralization-related genes (osteocalcin; OCN, Runt-related transcription factor-2; Runx2, collagen type 1; COL I, alkaline phosphatase; ALP). For statistical analysis, one-way analysis of variance (anova) and Tukey's honestly significant difference (HSD) tests were used. Results TBE (1/2), RS (1/2, 1/4), and HRS (1/2, 1/4) significantly decreased cell viability (P<0.001). AH (1/2, 1/4) and SS (1/2, 1/4) had similar cell viability to the control at 30h. All tested materials significantly decreased cell viability when compared to the control group except AH (1/2, 1/4) and SS (1/4) at 90h. All of the tested sealers reduced COL I mRNA expressions when compared to the control. SS was associated with significant increases in OCN and Runx2 mRNA expressions when compared to the control (P<0.001). Whereas all of the dilutions of TBE, RS and HRS significantly decreased BSP mRNA expressions (P<0,001), 1/2 and 1/4 dilutions of SS increased BSP mRNA expression (P<0,001). Except the 1/4 dilutions of AH and SS, all the sealer dilutions significantly reduced ALP mRNA expression in cementoblasts (P<0,001). Conclusions SimpliSeal and AH Plus resulted in more favourable response to cementoblasts because of their regulation potential on the mineralized tissue-associated protein's mRNA expressions.Öğe Sealing properties of four different post systems.(INT AMER ASSOC DENTAL RESEARCHI A D R/A A D R, 2003) Ozturk, A. N.; Usumez, A.; Cobankara, F. Kont; Eskitascioglu, G.; Belli, S.[Abstract not Available]
