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Öğe ADMA and total oxidant status in saliva(WILEY-BLACKWELL, 2013) Unlu, A.; Taner, A.; Unlu, N.; Ure, Z.; Korucu, E. N.[Abstract not Available]Öğe Bond Strength of Self-etch Adhesives After Saliva Contamination at Different Application Steps(OPERATIVE DENTISTRY INC, 2013) Cobanoglu, N.; Unlu, N.; Ozer, F. F.; Blatz, M. B.This study evaluated and compared the effect of saliva contamination and possible decontamination methods on bond strengths of two self-etching adhesive systems (Clearfil SE Bond [CSE], Optibond Solo Plus SE [OSE]). Flat occlusal dentin surfaces were created on 180 extracted human molar teeth. The two bonding systems and corresponding composite resins (Clearfil AP-X, Kerr Point 4) were bonded to the dentin under six surface conditions (n=15/group): group 1 (control): primer/bonding/composite; group 2: saliva/drying/primer/ bonding/composite; group 3: primer/saliva/ rinsing/drying/primer/bonding/composite; group 4: primer/saliva/rinsing/drying/bonding/ composite; group 5: primer/bonding (cured)/ saliva/rinsing/drying/primer/bonding/composite; group 6: primer/bonding (cured)/saliva/removing contaminated layer with a bur/rinsing/ drying/primer/bonding/composite. Shear bond strength was tested after specimens were stored in distilled water at 37 C for 24 hours. One-way analysis of variance and Tukey post hoc tests were used for statistical analyses. For CSE, groups 2, 3, and 4 and for OSE, groups 6, 2, and 4 showed significantly lower bond strengths than the control group (p<0.05). CSE groups 5 and 6 and OSE groups 3 and 5 revealed bond strengths similar to the control. When saliva contamination occurred after light polymerization of the bonding agent, repeating the bonding procedure recovered the bonding capacity of both self-etch adhesives. However, saliva contamination before or after primer application negatively affected their bond strength.Öğe The effect of different restoration techniques on the fracture resistance of endodontically-treated molars(OPERATIVE DENTISTRY INC, 2008) Cobankara, F. K.; Unlu, N.; Cetin, A. R.; Ozkan, H. B.Aim: This study compared the fracture resistance of endodontically-treated mandibular molars with mesio-occluso-distal (MOD) cavities restored using different restoration techniques. Methodology: Sixty sound extracted mandibular molars were randomly assigned to six groups (n=10). Group 1 did not receive any preparation. The teeth in Groups 2-6 received root canal treatment and a MOD cavity preparation. The teeth in Group 2 were kept unrestored. Group 3 was restored conventionally with amalgam. Group 4 was restored with a dentin bonding system (DBS, Clearfil SE Bond) and resin composite (CR) (Clearfil Photoposterior). Group 5 was restored with indirect hybrid ceramic inlay material (Estenia). In Group 6, polyethylene ribbon fiber (Ribbond) was inserted into cavities in a buccal-to-lingual direction and the teeth were then restored with DBS and CR. After finishing and polishing, the specimens, except for Group 2, were loaded to failure by a chewing simulation device (60,000 cycles x 50 N load, 1.3 Hz frequency) in an artificial environment at 37 degrees C. Each tooth was subjected to compressive loading perpendicular to the occlusal surface at a crosshead speed of 1 mm/minute. The mean loads necessary to fracture were recorded in Newtons and the results were statistically analyzed. Results: The mean fracture values were as follows: Group 1: 2485.3 +/- 193.9(a), Group 2: 533.9 +/- 59.4(b), Group 3: 1705.8 +/- 135.7(c), Group 4: 2033.3 +/- 137.6(cd), Group 5: 2121.3 +/- 156.5(d), Group 6: 1908.9 +/- 132.2(cd). There were statistically significant differences between the groups annotated with different letters. Thus, Group 1 (intact teeth) had the greatest fracture resistance and Group 2 (non-restored teeth) the poorest. No statistically significant differences were found between Groups 3 (amalgam), 4 (resin composite) and 6 (polyethylene ribbon fiber reinforced composite) (p>0.05). Group 5 (indirect hybrid ceramic inlay) had greater fracture resistance than Group 3 (p<0.05). Conclusions: Within the limitations of this study, although all of the restoration groups were stronger than the prepared-only group, none of the restoration techniques tested was able to completely restore the fracture resistance lost from MOD cavity preparation. However, use of indirect hybrid inlay restorations in these teeth may be recommended, because this restoration technique indicated more favorable fracture failure modes than other restoration techniques used in this study and particularly greater fracture strength than amalgam restorations. The promising result of indirect hybrid inlay restorations may need to be confirmed by long-term clinical studies.Öğe Effect of Er,Cr:YSGG Laser on the Microtensile Bond Strength of Two Different Adhesives to the Sound and Caries-affected Dentin(OPERATIVE DENTISTRY INC, 2009) Ergucu, Z.; Celik, E. U.; Unlu, N.; Turkun, M.; Ozer, F.Objective: This study examined the effect of Er,Cr:YSGG laser irradiation on the microtensile bond strength (pTBS) of a three-step etch-and-rinse and a two-step self-etch adhesive to sound and caries-affected dentin. Methods: Sixteen freshly extracted human molars with occlusal dentin caries were used. The caries lesion was removed by one of the following methods: conventional treatment with burs or Er,Cr:YSGG laser (Waterlase MD, Biolase). The adhesive systems (AdheSE, Ivoclar Vivadent and Scotchbond Multi Purpose, 3M ESPE) were applied to the entire tooth surface according to the manufacturers' instructions. Resin composites were applied to the adhesive-treated dentin surfaces and light-cured. Each tooth was sectioned into multiple beams with the "non-trimming" version of the microtensile test. The specimens were subjected to microtensile forces (BISCO Microtensile Tester, BISCO). The data was analyzed by three-way ANOVA and independent t-tests (p=0.05). Results: Er,Cr:YSGG laser irradiation exhibited similar pTBS values compared to that of conventional bur treatment, regardless of the adhesive system and type of treated dentin. The self-etch system revealed lower mu TBS values, both with conventional and laser treatment techniques, compared to the etch-and-rinse adhesive in sound and caries-affected dentin (p<0.05). Conclusion: Er,Cr:YSGG laser irradiation did not negatively affect the bonding performance of adhesive systems to sound and caries-affected dentin.Öğe A Five-Year Clinical Evaluation of Direct Nanofilled and Indirect Composite Resin Restorations in Posterior Teeth(OPERATIVE DENTISTRY INC, 2013) Cetin, A. R.; Unlu, N.; Cobanoglu, N.Aim: To assess the clinical efficacy of posterior composite resin restorations placed directly and indirectly in posterior teeth after five years. Materials and Methods: A total of 108 cavities in 54 patients were restored with three direct composite resins (Filtek SupremeXT [FSXT], Tetric Evo Ceram [TEC], AELITE Aesthetic [AA]) and two indirect composite resins (Estenia [E] and Tescera ATL [TATL]). All restorations were evaluated by two examiners using the United States Public Health Service criteria at baseline and five years after placement. Statistical analysis was completed with Fisher exact and McNemar chi(2) tests. Results: At baseline, 4% (five) of the restored teeth presented postoperative sensitivity; however, only one of them (a member of the E group) required canal treatment and replacement after two years. At the five-year evaluation, all restorations were retained, with Alpha ratings at 100%. Only one tooth (in the TEC group) required replacement after three years due to secondary caries. Color match, surface texture, and marginal integrity were predominantly scored as Alpha after five years for all groups. After that time, marginal discoloration was scored as Alpha in 64% of AE restorations, 70% of TATL restorations, 73% of E restorations, and 87% of FSXT restorations. There were no Charlie scores recorded for any of the restorative systems. Conclusions: Under controlled clinical conditions, indirect composite resin inlays and direct composite resin restorations exhibited an annual failure rate of 2.5% and 1.6%, respectively, after five years. Therefore, the investigated materials showed acceptable clinical performance, and no significant differences were found among them.Öğe Influence of Operator Experience on In Vitro Bond Strength of Dentin Adhesives(Quintessence Publishing Co Inc, 2012) Unlu, N.; Gunal, S.; Ulker, M.; Ozer, F.; Blatz, M. B.Purpose: To examine the influence of operator experience level on shear bond strength (SBS) of a self-etching adhesive (Clearfil SE Bond [CSE], Kuraray) and an etch-and-rinse adhesive (Single Bond [SB], 3M ESPE). Materials and Methods: Flat dentin surfaces were created on 120 extracted human third molars. Bonding agents and composite resin were applied and light cured according to manufacturers' directions (n = 15). Four operators with different levels of experience in operative dentistry performed the same specimen preparation steps independently: group 1: specialist in operative dentistry; group 2: post-graduate student; group 3: undergraduate dental student; group 4: private general practitioner. Specimens were stored in distilled water for 24 h at 37 degrees C before SBS testing. Statistical analyses were carried out with Mann-Whitney U- and Kruskall-Wallis tests. Results: For CSE, mean SBS and standard deviations were: (1) 54.4 +/- 15.6(a), (2) 55.3 +/- 7.6(a), (3) 49.4 +/- 10.5(ab), (4) 41.6 +/- 13.1(b). For SB, they were: (1) 28.6 +/- 10.3(c), (2) 32.7 +/- 11.2(c), (3) 17.5 +/- 5.6(d), (4) 24.4 +/- 9.5(cd). Groups with the same superscript letters are not significantly different. CSE showed higher bond strengths than SB in all groups (p < 0.05). There was no significant difference in mean bond strengths between groups 1 and 2 for each adhesive (p > 0.05). Depending on the adhesives, groups 3 and 4 were significantly different from groups 1 and 2, but not different from each other. Conclusion: Operator experience influences dentin bond strength values of dentin adhesives. An increased level of experience with a specific adhesive system and the associated application procedures correlates with higher SBSs.Öğe Three Dimensional Microscopic Investigation of Resin/Cavity Wall Integrity.(Amer Assoc Dental Research, 2000) Özer, F.; Şengün, A.; Belli, Sema; Unlu, N.; Alkaya, F.[Abstract not Available]
