Yazar "Orucoglu, Hasan" seçeneğine göre listele
Listeleniyor 1 - 11 / 11
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Effect of a new restoration technique on fracture resistance of endodontically treated teeth(BLACKWELL PUBLISHING, 2008) Sengun, Abdulkadir; Cobankara, Funda Kont; Orucoglu, HasanThe aim of the study was to investigate the effect of a new fiber-reinforced composite restoration technique on fracture resistance in endodontically treated premolars. Eighty sound extracted human mandibular premolars were assigned to four groups (n = 20). Group 1 did not receive any treatment. In groups 2, 3 and 4, the teeth received root canal treatment and a mesio-occluso-distal cavity preparation. Group 2 was kept unrestored. Group 3 was restored with a dentin bonding system and composite resin. In group 4, a piece of polyethylene ribbon fiber was inserted into the groove in a buccal to lingual direction during the restoration of teeth with dentin bonding system and composite resin. After finishing and polishing, the specimens were stored in 100% humidity at 37 degrees C for 24 h and placed at an angle of 45 degrees to the long axis of the tooth and subjected to compressive loading in a universal testing machine at a crosshead speed of 0.5 mm min(-1). The load necessary to fracture the samples was recorded in Newton (N) and submitted to Kruskal-Wallis ANOVA and Mann-Whitney U-test. The fracture strength of the teeth reinforced with a combination of polyethylene fiber and composite resin were not significantly different than those that were restored with only composite resin (P > 0.05). However, most of the failure modes of the reinforced teeth were limited to the level of the enamel, while the other three groups showed fractures generally at the level of the dentin, cemento-enamel junction or more below (P < 0.05). Therefore, polyethylene ribbon fiber-reinforced composite resin restorations seemed a more reliable restorative technique than traditional composite restorations for extensive cavities.Öğe Effect of Er,Cr:YSGG Laser Irradiation on the Apical Sealing Ability of AH Plus/Gutta-Percha and Hybrid Root Seal/Resilon Combinations(MOSBY-ELSEVIER, 2010) Onay, Emel Olga; Orucoglu, Hasan; Kiremitci, Arlin; Korkmaz, Yonca; Berk, GizemObjective. The objective of this study was to evaluate the sealing ability of 2 different resin-based endodontic filling systems after smear layer removal with 2 different techniques. Study design. Extracted human single-rooted teeth (n = 74) were instrumented using HERO Shaper rotary instruments and irrigated with 1 mL of 2.5% NaOCl between each instrument. Additionally, the canals received either an extra 3-minute rinse with 2 mL of 17% EDTA or a 40-second Er,Cr:YSGG laser treatment. The root canals were filled with either Hybrid Root Seal/Resilon combination or AH Plus/gutta-percha combination using lateral condensation technique (n + 11). Apical leakage quantity was measured with the computerized fluid filtration meter at 1 and 4 weeks. One root from each group, which was not submitted to the fluid filtration test, was selected for scanning electron microscopy (SEM) analysis. Statistical analysis was performed using 3-way ANOVA and the post hoc Tukey HSD test (alpha = 0.05). Results. A significant decrease was observed in the microleakage values of all the experimental groups tested with time (P < .0001). EDTA + AH Plus/gutta-percha combination exhibited the least microleakage, whereas laser irradiation + Hybrid Root Seal/Resilon combination showed the greatest microleakage at each of the 2 time periods. Each experimental combination exhibited architecture in SEM that seemed to correlate with its sealing performance. Conclusion. Er, Cr: YSGG laser treatment does not enhance the sealing ability of the sealers compared with EDTA application. The root canal adaptation and sealing ability of the Hybrid Root Seal/Resilon combination is not superior to that of the AH Plus/gutta-percha combination.Öğe The effect of fiber placement or flowable resin lining on microleakage in Class II adhesive restorations(QUINTESSENCE PUBLISHING CO INC, 2007) Belli, Sema; Orucoglu, Hasan; Yildirim, Cihan; Eskitascioglu, GurcanPurpose: The aim of this in vitro study was to evaluate the effect of two fibers (polyethylene or glass) and a flowable resin liner on microleakage in Class 11 adhesive restorations. Materials and Methods: Class 11 adhesive cavities were prepared on mesial and distal surfaces of 40 extracted sound human molars. The cavity margins were below or above the CEJ. The teeth were randomly divided into four groups according to the restoration technique: group 1: restored with a resin composite (AP-X, Kuraray) in bulk after SE Bond (Kuraray) treatment; group 2: flowable resin liner (Protect Liner F, Kuraray) was used before composite restoration; in group 3, a polyethylene fiber (Ribbond) and in group 4, a glass fiber (everStick NET, StickTech) was placed into the bed of flowable resin before composite restoration. Samples were finished, stored in distilled water for 7 days at room temperature, and then thermocycled for 300 cycles between 5 degrees C and 55 degrees C. After sealing the apices, the teeth were varnished within 1 mm of the margins and placed in 0.5% basic fuchsin dye for 24 h at 37 degrees C. After rinsing, the teeth were sectioned longitudinally through the restorations and microleakage was evaluated with a stereomicroscope. Marginal penetration was scored on a 0 to 4 scale, and the data were statistically analyzed using Kruskal-Wallis and the Mann-Whitney U-test. Results: Flowable resin, everStick NET, and Ribbond THM used in combination with flowable resin significantly reduced leakage at occlusal margins in cavities with enamel margins (p < 0.05). When the leakage values on cervical dentin margins were evaluated, there was no statistically significant difference among the tested groups (p > 0.05). Conclusion: Use of flowable composite alone or in combination with polyethylene or glass fibers reduces occlusal leakage in Class 11 adhesive cavities with enamel margins.Öğe Effect of Immediate and Delayed Post Preparation on Apical Microleakage by Using Methacrylate-based EndoREZ Sealer with or without Accelerator(ELSEVIER SCIENCE INC, 2008) Cobankara, Funda Kont; Orucoglu, Hasan; Ozkan, Hatice Buyukozer; Yildirim, CihanThe purpose of this study was to evaluate the effect of immediate and delayed post space preparation on the apical sealing ability of EndoREZ, a methacrylate-based dual-cured resin sealer, with or without accelerator. Fifty extracted human teeth were endodontically prepared and randomly divided into 6 groups. Teeth in experimental groups 1, 2, 3, and 4 (n = 10) were filled with resin-coated gutta-percha and either EndoREZ with accelerator (A+) or EndoREZ without accelerator (A-) by the lateral compaction technique. In group1 (A+) and group2 (A-), the post space was prepared immediately at the time of obturation. In groups 3 (A+) and 4 (A-), the post space was prepared after storage in 100% humidity at 37 degrees C for 1 week. Groups 5 and 6 (n = 5) represented positive and negative control groups, respectively. Leakage was determined by computerized fluid filtration device. Complete leakage was observed in group 5, and no leakage was evident in group 6 (P = 1.000). In experimental groups, mean apical microleakage values (mu L/cmH(2)O/ min(-1)) were as follows: group 1, 2.77 +/- 0.79(a); group 2, 2.88 +/- 1.38(a); group 3, 19.95 +/- 7.85(c); group 4, 6.20 +/- 2.09(b) (different letters indicate significantly different groups, P < .005). Immediate post space preparation achieved better sealing than delayed post preparation at the apical end, regardless of whether the EndoREZ accelerator was used. There was no significant difference between the (A+) and (A-) in immediate post space preparation. However, more leakage was found when using (A+) than (A-) in delayed post preparation. Under the conditions of this study, it was concluded that EndoREZ accelerator seems not to provide clinicians with any advantage for rapid transition from endodontic treatment to post-endodontic restorative procedures immediately after completion of root canal therapy. (J Endod 2008;34:1504-1507)Öğe Effect of the angle of apical resection on apical leakage, measured with a computerized fluid filtration device(MOSBY-ELSEVIER, 2011) Garip, Hasan; Garip, Yildiz; Orucoglu, Hasan; Hatipoglu, SedaObjective. We determined the effect of the angle of apical resection on apical leakage using a computerized fluid filtration meter with a laser system and a digital air pressure regulator in 46 extracted single-rooted human teeth. Orthograde endodontic treatment was performed. The root canals were prepared up to a size 50 K-type file with 17% EDTA solution (Roth International, Chicago, IL) and 5% NaOCl solution as the irrigant. Gates Glidden burs (Maillefer Instruments, Ballaigues, Switzerland) were used to flare the coronal two thirds of the canal. All canals were dried with paper points and then obturated using cold lateral condensation (except for the positive controls) of gutta-percha points and AH plus (Dentsply DeTrey, Konstanz, Germany). All 40 roots were sectioned 3 mm from the apex. Forty teeth were assigned randomly into 1 of 4 experimental groups of 10 teeth each: in group 1, the teeth were resected apically (90 degrees angle) and the cavities were obturated with mineral trioxide aggregate (MTA); in group 2, after apical resection (90 degrees angle), a root-end cavity was prepared using ultrasonic diamond retrotips and the cavities were obturated with MTA; in group 3, the teeth were resected apically (similar to 45 degrees angle) and the cavities were obturated with MTA; and in group 4, after apical resection (similar to 45 degrees angle), a root-end cavity was prepared using ultrasonic diamond retrotips and the cavities were obturated with MTA. An additional 6 teeth were used as controls (3 each, negative and positive controls). Apical leakage was measured using a computerized fluid filtration meter with a laser system. Results. The mean apical microleakage was 2.0 +/- 0.4 x 10(-4), 1.6 +/- 0.6 x 10(-4), 1.6 +/- 0.9 x 10(-4), and 1.8 +/- 0.7 x 10(-4) mu L/cmH(2)O/min(-1) at 1.2 atm, in groups 1 to 4, respectively. Although the mean apical microleakage was greater in group 1, the differences among the 4 groups were not statistically significant (P > .05). Conclusions. The results of these in vitro studies showed that when an adequate retrograde cavity depth is prepared, variation in the root-end cutting angle does not necessarily cause any difference in microleakage. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011;111:e50-e55)Öğe Effect of unintentionally extruded calcium hydroxide paste including barium sulfate as a radiopaquing agent in treatment of teeth with periapical lesions: Report of a case(ELSEVIER SCIENCE INC, 2008) Orucoglu, Hasan; Cobankara, Funda KontCalcium hydroxide [Ca(OH)(2)] has been widely used as short- or long-term intracanal antibacterial dressing material after endodontic treatment. in general when used in endodontics, Ca(OH)(2) paste is composed of the powder, a vehicle, and a radiopacifier. To provide radiopacity, barium sulfate (BaSO4) powder is usually added to the paste. In this case report, BaSO4:Ca(OH)(2) powders (ratio 1:8) and distilled water were mixed and applied as dressing material after root canals of mandibular left canine and premolar teeth with periapical lesions. However, the prepared paste was unintentionally extruded into the periapical lesion during application. The patient was seen 12 and 36 months later at which point periapical healing was evaluated. At this time, it was observed that the periapical lesion had disappeared, but white radiopaque spots were seen at the place where calcium hydroxide remnants had originally been present. The presented case report reveals that when Ca(OH)(2) paste that included BaSO4 was applied as an intracanal dressing and extruded through the periapical lesion associated with pulpless teeth, it had no detrimental effect. However, healing might take longer when Ca(OH)(2) paste including BaSO4 is used, so deliberate overextension is not advocated.Öğe Evaluation of the Effect of Four Self-Etching Adhesives on Dentin Permeability(WILEY-LISS, 2009) Orucoglu, Hasan; Belli, SemaObjective: The aim of this study was to evaluate the effect of two two-step and two single-step self-etching adhesives on dentin permeability using a computerized fluid filtration (CFF) test method. Methodology: Forty recently extracted sound human molar teeth were sectioned at the mid level of the crown to obtain dentin discs of 1 +/- 0.2 mm. A total of 40 discs were obtained and randomly divided into four groups (n = 10). The permeability of the discs was measured using the CFF test method before and after application of the following self-etching adhesives: Hybrid Bond, G-Bond, AdheSE, and Protect Bond. Fluid movement measurements were made at 2-min intervals for 8 min, and a mean of the values obtained was calculated for each specimen. Results: The in vitro fluid conductance of dentin discs treated with Hybrid Bond and AdheSE were lower than the dentin discs treated with G-Bond and Protect Bond (p < 0.05.). Conclusion: 1-Treating dentin discs with self-etching adhesives caused significant reduction of dentin permeability. 2-All self-etching adhesives allowed diffusion of distilled water. However, AdheSE and Hybrid Bond showed the lowest permeability. (C) 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 90B: 110-115, 2009Öğe The evaluation of the influence of using MTA in teeth with post indication on the apical sealing ability(MOSBY-ELSEVIER, 2009) Yildirim, Tahsin; Tasdemir, Tamer; Orucoglu, HasanObjectives. The aim of this study was to evaluate the influence of using MTA in teeth with post-core indication and to compare it with the immediate or delayed post space preparation on the integrity of apical seal in teeth filled with gutta-percha and sealer. Study design. Fifty-one single-rooted freshly extracted human maxillary incisor teeth were selected. The crowns of the teeth were removed to a length of 14 mm and canals were prepared by using K-files with the step-back technique. The teeth were randomly divided into 3 groups of 15 specimens each. Group A was filled with gutta-percha and sealer using lateral compaction, and post space was prepared immediately using a heated instrument. Specimens in Group B were filled with the same materials as Group A and post space was prepared after 1 week with Gates-Glidden drills. Group C was filled with MTA as an apical 5-mm filling. In all groups, materials were left in the root canals at the apical 5-mm level. The remaining 6 teeth were used as controls. The microleakage values of each group were measured after 1 month, using a computerized fluid filtration method. Results. The MTA (Group C) showed less microleakage than immediate and delayed post space preparation methods (Group A, B) in 1 month, and this difference was found to be statistically significant (P < .005). Additionally, no statistically significant difference was determined between Group A and Group B (P < .05). Conclusion. These results suggest that MTA can be used in the root canals as apical filling material in teeth with post-core indication. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 108: 471-474)Öğe Long-term Evaluation of the Influence of Smear Layer on the Apical Sealing Ability of MTA(ELSEVIER SCIENCE INC, 2008) Yildirim, Tahsin; Orucoglu, Hasan; Cobankara, Funda KontThe aim of this in vitro study was to investigate the effect of the smear layer on apical microleakage in teeth obturated with mineral trioxide aggregate (MTA). Fifty single-rooted central maxillary teeth were used in this study. All teeth were instrumented to size 60 by using the step-back technique, The selected teeth were randomly divided into 2 groups (n = 20). In the first group (smear [+]), the teeth were irrigated with only NaOCl (5.25%). In the second group (smear [-]), the teeth were irrigated with ethylenediaminetetraacetic acid (EDTA) (17%) and NaOCl (5.25%) to remove the smear layer. The teeth were then filled with MTA. The computerized fluid filtration method was used for evaluation of apical microleakage. The quantitative apical leakage of each tooth was measured after 2, 30, and 180 days. Statistical analysis was done with the Mann-Whitney U and Wilcoxon signed ranks tests. At the end of this study there was no difference in 2 days between the groups, but removal of the smear layer caused significantly more apical microleakage than when the smear layer was left intact for 30 and 180 days (P < .005). Within the constraints of this study it can be concluded that the apical microleakage of MTA is less when the smear layer is present than when it is absent. (J Endod 2008;34:1537-1540)Öğe Maxillary first molar with an unusual morphology: report of a rare case(MOSBY-ELSEVIER, 2008) Cobankara, Funda Kont; Terlemez, Arslan; Orucoglu, HasanVariations in dental anatomy are found in all teeth. Knowledge of these variations, particularly concerning the location and treatment of all canals, is very important for the success of endodontic therapy, because the inability to find and properly treat the root canals may cause failures. Variations in canal morphology, such as extra canals, apical ramifications, apical deltas, or lateral canals, are commonly encountered, and their incidence and significance have been well documented. However, the clinician should also be aware of the possibility of the existence of fewer root and/or canal numbers. The goal of this clinical article is to describe root canal treatment in a maxillary first molar with the unusual morphology of a single root and a single canal. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008; 106:e62-e65)Öğe Push-out bonding strengths of four different dowel systems luted with two different adhesive systems(TAYLOR & FRANCIS LTD, 2014) Orucoglu, Hasan; Yavuz, Tevfik; Demir, Necla; Ozturk, Nilgun; Ozturk, BoraThis in vitro study investigates the bonding capacity of resin cements to dowels, using the push-out bonding strength of four different dowel systems, namely, stainless steel dowels (SSD), resin-supported polyethylene fiber dowels (RSPFD), zirconia dowels (ZD), and superpost glass fiber dowels (GFD), luted in root canals, using two different resin cements, namely, Multilink Automix Cement and Clearfil Esthetic Cement. Ninety-six maxillary central incisor teeth were sectioned below the cementoenamel junction, and the roots were treated endodontically. Then the roots were placed into four groups, based on the dowel systems used. The roots were further placed into two subgroups, based on the cement type used as subgroup A and subgroup B. Push-out bonding tests were performed on the bonded specimens, which were cut into 1mm thick sections. A two-way ANOVA test and Tukey's HSD tests were performed. The push-out bonding strength values for SSD, ZD, and RSPFD were not significantly different (p>0.05). The means for GFD were significantly higher than the means for ZD (p<0.05) when Multilink Automix Cement was used. However, when Clearfil Esthetic Cement was used, the means for RSPFD were significantly higher (p<0.001) than the means for the other systems. When Clearfil Esthetic Cement was used, the RSPF dowel system provided significantly higher bonding strength values than the other systems.
