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Öğe Effect of EDTA and citric acid solutions on the microhardness and the roughness of human root canal dentin(ELSEVIER SCIENCE INC, 2005) Eldeniz, AU; Erdemir, A; Belli, SThe purpose of this study was to evaluate the effect of citric acid and EDTA solutions on the microhardness and the roughness of human root canal dentin. Forty-five human teeth sectioned longitudinally were used. Specimens were randomly divided into three groups of 30 teeth each and were treated as follows: (a) one molar (19%) citric acid (C6H8O7) for 150 s followed by 5.25% NaOCl; (b) 17% EDTA for 150 s and rinsed with 5.25% NaOCl; (c) rinsed with distilled water and served as control. Three groups were then divided into two subgroups of 15 specimens each. The specimens, in first subgroup were subjected to Vicker's testing whereas the second subgroup underwent surface roughness testing. The results were analyzed using one-way ANOVA and Tukey tests. Significant differences were observed in microhardness among the test groups, citric acid group being the least hard (p 0.05). Also, citric acid significantly increased surface roughness.Öğe The effect of fibre insertion on fracture resistance of root filled molar teeth with MOD preparations restored with composite(WILEY, 2005) Belli, S; Erdemir, A; Ozcopur, M; Eskitascioglu, GAim To evaluate the effect of using flowable composite with or without leno woven ultra high modulus polyethylene fibre reinforcement on fracture resistance of root filled mandibular molars with mesio-occluso-distal (MOD) preparations. Methodology Sixty sound extracted human mandibular molars were randomly assigned to five groups (n = 12). Group 1 did not receive any preparation. From groups 2 to 5, the teeth were root filled and MOD preparations were created. Group 2 remained unrestored. Group 3 was restored with a dentine bonding system (DBS; SE Bond, Kuraray, Japan) and composite resin (CR) (AP-X; Kuraray). In group 4, flowable composite resin (Protect Liner F; Kuraray) was used before restoring teeth with CR. In group 5, leno woven ultra high modulus polyethylene ribbon fibre (Ribbond, Seattle, WA, USA) was inserted into the cavities in a buccal to lingual direction and the teeth were then restored with DBS and CR. After finishing and polishing, the specimens were stored in 100% humidity at 37 degreesC for 1 day. Compressive loading of the teeth was performed using a universal testing machine at a crosshead speed of 0.5 mm min(-1). The mean load necessary to fracture the samples were recorded in newtons (N) and were subjected to analysis of variance (anova) and Tukey post-hoc test. Results The mean load necessary to fracture the samples in each group were (in N): group 1: 1676.75 +/-154.63(a), group 2: 376.51 +/- 37.36(b), group 3: 733.23 +/- 133.33(c), group 4: 786.48 +/- 145.34(c), group 5: 943.63 +/- 121.15(d). There were statistically significant differences between the groups annotated with different letters. Conclusions (i) Use of flowable composite resin under composite restorations had no effect on fracture resistance of root filled molar teeth with MOD preparations, (ii) use of polyethylene ribbon fibre under composite restorations in root filled teeth with MOD preparations significantly increased fracture strength.Öğe Effect of gutta-percha solvents on mineral contents of human root dentin using ICP-AES technique(LIPPINCOTT WILLIAMS & WILKINS, 2004) Erdemir, A; Eldeniz, AU; Belli, SThe purpose of this in vitro study was to evaluate the mineral contents of root-canal dentin before and after treatment with two commonly used gutta-percha solvents: chloroform and halothane. Twenty extracted human premolars, whose crowns and apical thirds had been removed, were used. Pulp tissues were removed and the teeth were randomly divided into two groups including 10 teeth each. Root canals were enlarged with Gates Glidden burs (#1, 2, and 3). Dentin chips were obtained and saved in plates to serve as a control. Root-canal-dentin walls were then treated with chloroform or halothane for 15 min. Dentin chips were again obtained using Gates Glidden burs (#4, 5, and 6). The levels of five elements, calcium, phosphorus, magnesium, potassium, and sulfur, in each specimen were analyzed using ICP-AES (inductively coupled plasma atomic emission spectrometry) technique. Changes in the levels of the chemical elements were recorded. Differences between the groups were statistically analyzed using Mann-Whitney U test. There was a significant decrease in Ca level and significant increase in Mg level after treatment with halothane (p < 0.05). There was a significant increase in Mg level after treatment with chloroform. The changes in other elements levels after treatment with gutta-percha solvents were minimal and statistically not significant (p > 0.05). As a result it was concluded that gutta-percha solvents have effect on mineral contents of root dentin.Öğe Effect of medications for root canal treatment on bonding to root canal dentin(LIPPINCOTT WILLIAMS & WILKINS, 2004) Erdemir, A; Ari, H; Gungunes, H; Belli, SUse of resin-based restorative materials recently has become widely accepted for treatment of endodontically treated teeth. However, some solutions routinely used during endodontic treatment procedures may have an effect on bond strengths of adhesive materials to root canal dentin. The purpose of this in vitro study was to evaluate the effect of various medications on microtensile bond strength to root canal dentin. Fourteen extracted human single-rooted teeth were used. The crowns and the pulp tissues were removed. The root canals were then instrumented and widened to the same size. The teeth were randomly divided into seven groups of two teeth each. The root canal dentin walls of the roots were treated with 5% sodium hypochloride (NaOCl), 3% hydrogen peroxide (H2O2), the combination of H2O2 and NaOCl, or 0.2% chlorhexidine gluconate for 60 s; or calcium hydroxide or formocresol for 24 h. The teeth in control group were irrigated with water. The root canals were obturated using C&B Metabond. After 24 h of storage in distilled water,serial 1-mm-thick cross-sections were cut, and approximately 12 samples were obtained from each group. Microtensile bond strengths to root canal dentin were then measured by using an Instron machine. The data were recorded and expressed as MPa. The results indicated that NaOCl, H2O2, or a combination of NaOCl and H2O2 treatment decreased bond strength to root canal dentin significantly (p < 0.05). The teeth treated with chlorhexidine solution showed the highest bond strength values (p < 0.05). In conclusion, chlorhexidine is an appropriate irrigant solution for root canal treatment before adhesive post core applications.Öğe Effect of solvents on bonding to root canal dentin(LIPPINCOTT WILLIAMS & WILKINS, 2004) Erdemir, A; Eldeniz, AU; Belli, S; Pashley, DHThe long-term success of resin cementation of post/cores is likely increased with improvement in resin-root canal dentin bonding. The adverse effect of some irrigation constituents (NaOCl, H2O2) or medications (eugenol) on the bond strengths of resins to dentin have been reported. The purpose of this in vitro study was to evaluate the effect of two gutta-percha solvents (chloroform versus halothane) on microtensile bond strength to root canal dentin. Thirty, extracted, human, single-rooted teeth were instrumented to a #70 file and randomly divided into 3 groups of 10 each. The root canals were treated with water, chloroform, or halothane for 60 s. All root canals were obturated using C&B Metabond. After 24 h of storage in distilled water, serial 1-mm-thick cross-sections were cut and trimmed. Microtensile bond strength to apical, middle, and coronal root canal dentin were measured using an Instron machine. Using pooled data, the results indicated that water-treated roots had significantly higher resin-dentin bond strengths compared with chloroform or halothane treatment groups (control: 23.9 MPa; chloroform: 18.3 MPa; halothane: 17 MPa; p < 0.05). Gutta-percha solvents have an adverse effect on bond strengths of adhesive cements to root canal dentin.Öğe Effect of the gutta-percha solvents on the microhardness and the roughness of human root dentine(WILEY, 2004) Erdemir, A; Eldeniz, AU; Belli, SThe purpose of this in vitro study was to evaluate the effect of gutta-percha solvents on the microhardness and the roughness of human root dentine. Forty-five recently extracted human mandibular anterior teeth were used. The teeth were sectioned longitudinally, embedded in acrylic resin and polished. Ninety specimens were divided into three groups containing 30 teeth each. In group 1, the specimens were treated with chloroform for 15 min. In group 2, the specimens were treated with halothane for 15 min. In group 3, distilled water was used and this group was served as control. All groups were then divided into two subgroups of 15 specimens each. The specimens, in groups 1a, 2a and 3a, were submitted to Vicker's microhardness indentations. Groups 1b, 2b and 3b were used for determination of the roughness of root dentine. The data were recorded as Vicker's numbers and Ra, mum for roughness test. The results were then analysed by one-way ANOVA and post hoc Tukey tests. The results indicated that chloroform and halothane did not affect the microhardness and the roughness of root dentine (P > 0.05).Öğe Effects of endodontic irrigation solutions on mineral content of root canal dentin using ICP-AES technique(ELSEVIER SCIENCE INC, 2005) Ari, H; Erdemir, AThe aim of this in vitro study was to evaluate mineral content of root canal dentin after treatment with several endodontic irrigation solutions. Sixty mandibular anterior teeth extracted for periodontal reasons used. The crowns of the teeth were removed at the cementoenamel junction. Pulp tissues were removed and the teeth were randomly divided into six groups including 10 teeth each. Root canals were enlarged with gates-glidden burs (# 1, 2, and 3). The groups were treated as follows: group 1, 0.2% chlorhexidine gluconate for 15 min; group 2, 3% H2O2 for 15 min; group 3, 17% EDTA for 15 min; group 4, 5.25% NaOCl for 15 min; group 5, 2.5% NaOCl for 15 min; and group 6, distilled water (control). Dentin chips were obtained using gates-glidden burs (# 4, 5, and 6). The levels of five elements calcium, phosphorus, magnesium, potassium, and sulfur in each specimens were analyzed using ICP-AES (inductively Coupled Plasma Atomic Emission Spectrometry) technique. Changes in the levels of the chemical elements were recorded. The results were then statistically analyzed by one-way ANOVA and Tukey tests. There was a significant decrease in the calcium and phosphorus levels after treatment with all irrigation solutions except for 5.25% NaOCl when compared with the control group (p < 0.05). The K, Mg, and S level changes were not statistically significant (p > 0.05). It has been concluded that endodontic irrigation solutions have an effect on mineral contents of root dentin.Öğe Evaluation of the effect of endodontic irrigation solutions on the microhardness and the roughness of root canal dentin(ELSEVIER SCIENCE INC, 2004) Ari, H; Erdemir, A; Belli, SThe purpose of this study was to evaluate the effect of 0.2% chlorhexidine gluconate on the microhardness and roughness of root canal dentin compared with widely used irrigation solutions. Ninety, mandibular, anterior teeth extracted for periodontal reasons were used. The crowns of the teeth were removed at the CEJ. The roots were separated longitudinally into two segments, embedded in acrylic resin, and polished. A total of 180 specimens were divided into 6 groups of 30 teeth at random according to the irrigation solution used: group 1: 5.25% NaOCl for 15 min; group 2: 2.5% NaOCl for 15 min; group 3: 3% H2O2 for 15 min; group 4: 17% EDTA for 15 min; group 5: 0.2% chlorhexidine gluconate for 15 min; and group 6: distilled water (control). Each group was then divided into 2 subgroups of 15 specimens: groups 1a, 2a, 3a, 4a, 5a, and 6a were submitted to Vickers microhardness indentation tests; groups 1b, 2b, 3b, 4b, 5b, and 6b were used for determination of the roughness of root dentin. The data were recorded as Vickers numbers and Ra, mum for roughness test. The results were analyzed statistically by using one-way ANOVA and Tukey tests. The results indicated that all the irrigation solutions except chlorhexidine significantly decreased microhardness of root canal dentin (p < 0.05); 3% H2O2 and 0.2% chlorhexidine gluconate had no effect on roughness of the root canal dentin (p > 0.05). Although there are many other factors for irrigation solution preference, according to the results of this study, 0.2% chlorhexidine gluconate seems to be an appropriate endodontic irrigation solutions because of its harmless effect on the microhardness and roughness of root canal dentin.Öğe Reinforcement effect of polyethylene fibre in root-filled teeth: comparison of two restoration techniques(WILEY, 2006) Belli, S; Erdemir, A; Yildirim, CTo compare in vitro two different fibre placement techniques on reinforcement of root-filled molar teeth with mesio-occluso-distal (MOD) cavities. Fifty sound extracted human mandibular molars were used (n = 10). Group 1 served as control. From group 2-5, endodontic access and standard MOD cavities were prepared. Following root canal treatment, group 2 was kept unrestored. In groups 3 and 4, the teeth were restored with composite resin (AP-X; Kuraray, Japan). A groove was prepared on occlusal surface of the finished restorations in group 4 from buccal to lingual direction. Polyethylene woven fibre (Ribbond; Seattle, WA, USA) was inserted in the groove in combination with flowable resin that was cured for 20 s and covered with composite resin. Cavity surfaces were covered with flowable resin in group 5, and polyethylene fibre was placed into the bed of resin in a buccal to lingual direction before the composite restoration was placed. All specimens were stored in 100% humidity at 37 degrees C for 24 h. Compressive loading of the teeth was performed by a universal testing machine at a crosshead speed of 0.5 mm min(-1) until failure. The data were recorded in Newton and submitted to ANOVA and Tukey post hoc test. The mean load necessary to fracture the samples in each group was: G1: 1671.57 +/- 131.54(a); G2: 375.21 +/- 34.30(b); G3: 749.47 +/- 124.54(c); G4: 1224.36 +/- 132.17(d); G5: 926.88 +/- 118.28(e). Different superscript letters demonstrate significant difference between groups. Polyethylene fibre use over or under MOD composite restorations significantly increased fracture strength. However, when the fibre was placed on the occlusal surface of the restoration in buccal to lingual direction, significantly higher fracture resistance was observed.Öğe Shear bond strength of three resin based sealers to dentin with and without the smear layer(ELSEVIER SCIENCE INC, 2005) Eldeniz, AU; Erdemir, A; Belli, SBond strength of root canal sealers to dentin is an important property for the integrity of the sealings of root-canals. The purpose of this study was to test shear bond strength of three endodontic sealers (Diaket, AH Plus and Endo-REZ). The coronal two thirds of ninety extracted human third molars were removed. The smear layer of the exposed dentin surfaces were removed using 17% EDTA followed by 5.25% NaOCl and the teeth were randomly divided into two groups (n = 45). Group 1 was kept as control and in group 2, uniform smear layer was created using waterproof polishing papers. Three-mm long sections of polyethylene tubing were filled with freshly mixed sealer and placed on the dentin surfaces for conducting a shear bond strength test. The data was calculated as MPa and was statistically analyzed using a two way ANOVA, Kruskal-Wallis and Mann-Whitney U tests. A significant difference was found among the bond strength of the sealers, smear layer, and control groups. AH Plus sealer showed the highest bond strength in smear layer removed surfaces (p < 0.05). Pretreatment with EDTA/NaOCl affected bond strength of AH Plus. AH Plus had the highest bond to dentin with or without smear layer.
