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Conjugated polymers are promising cost-effective, lightweight, and flexible electrode materials. 3,5-Dinonyl-2,6-di(thiophene-2-yl)dithieno[3,2-b : 2 ',3 ' d]thiophene (M1) as a donor and 4,4 '-dinonyl-5,5 '-di(thiophen-2-yl)-2,2 '-bithiazole (M2) as an acceptor were synthesized and their polymers poly(3,5-dinonyl-2,6-di(thiophene-2-yl)dithieno[3,2 b : 2 ',3 '-d]thiophene) (P1) and poly(4,4 '-dinonyl-5,5 '-di(thiophen-2-yl)-2,2 '-bithiazole) (P2) were obtained via electropolymerization on ITO/glass electrode surface in ACN : DCM (1 : 3 v/v) solution, containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF(6)). Then, a third polymer as a co-polymer (P3) was synthesized through electropolymerization of a mixture of the monomers M1 and M2 in 1 : 1 ratio. All the polymers were characterized by UV-Vis, CV and CV-UV measurements. Moreover, capacitor properties of the polymers by potentiostatic electrochemical impedance spectroscopy (EIS) was performed. The polymers P1, P2 and P3 exhibited absorptions at 456, 453 and 519 nm in neutral state and their optical band gaps were determined to be 2.17, 2.53 and 1.95 eV, respectivetly. EIS measurements indicated that P3 had the highest current density, having lower resistance.

WOS: 000453871900008, PubMed ID: 30295386, The aim of the study was to evaluate of surface roughness and color changes of the resin-based five restorative dental materials after aging in liquids at different pH values. Totally 250 specimens were prepared, including 50 specimens for the each material group from five different restorative materials (G1[Filtek Z550], G2[Beautifil II], G3[Vertise Flow], G4[Dyract XP], G5[GCFujiIILC]), using the 10-mm diameter and 2-mm thickness molds. A total of 50 specimens in the each group, were divided into five subgroups (n = 10) to be immerse into five liquids at different pH. After initial color and roughness measurements, samples were stored in the same liquids for 7 and 14 days and all of the measurements were repeated on the 7th and 14th days. scanning electron microscopy and atomic force microscopy analyses were performed in the all groups. When the color change(Delta E) results are examined statistically; most of the Delta E is in Fuji II LC; and at least in Filtek Z550, it was determined that cola and gastric acid had the greatest effect on Delta E averages and showed significant differences (p < .05). When the average roughness values(Ra) are analyzed statistically, the highest values were found in Fuji II LC and the lowest values were found in Filtek Z550 (p < .05). The liquids which had the highest roughness average (Delta Ra) were statistically significant and gastric acid and orange juice were the most effective ones (p < .05). Asidic beverages significantly increased the surface roughness and discoloration of dental restorative materials. Research Highlights The results of this research showed that dental restorative materials, which are resin-based, affected both the color and surface roughness after waiting in the low pH value beverages. These results are supported with the scanning electron microscopy and atomic force microscopy images in our research. Clinically, this situation will create esthetic and functional problems in the dental filling restorations. For this reason, the results of this study seem to be important and we think that this article could be contribute to the literature.

WOS: 000471903000009, PubMed ID: 30866096, The aim of this in-vitro study was to evaluate microtensile bond strength (mu TBS) of two different self-adhesive composites (SACs) on the permanent dentin by applying five different universal adhesive systems. In this study, two different SACs [Vertise Flow (VF), Fusio Liquid Dentin (FLD)] and five different bonding systems [Clearfil Universal Bond Quick (CUB), Single Bond Universal (SBU), All Bond Universal (ABU), Prime Bond Universal (PBU), Futurabond U (FBU)] were used. A total of 22 groups were created in which SACs were applied without adhesive and with five different universal bonding agents in total-etch (TE) and self-etch (SE) modes. Two hundred and forty test sticks were obtained using 48 healthy human molar teeth in total with groups having 10 samples each. The mu TBS test was applied to each sample in the Universal test device and the data obtained were analyzed statistically by variance analysis and Tukey HSD test. In addition, the resin-dentin interface and fractures modes in the groups were examined by SEM. Upon examining the mu TBS results, the highest values were seen in the use of SBU adhesive in TE mode in VF group, while the lowest values were seen in the FLD control group. The difference between the control and experimental groups was found statistically significant (p < .05). Upon comparing the control groups with each other, it was seen that VF group had higher mu TBS values than FLD group and the difference between the groups was found statistically significant (p < .05). The mu TBS results and SEM images of the study showed that the use of SACs with universal adhesive systems provides a more effective bond strength., Cumhuriyet University [DIS-200], Cumhuriyet University, Grant/Award Number: DIS-200

WOS: 000468584500006, PubMed ID: 30964722, Aim: This in vitro study was aimed to investigate the performance of the new caries detection tools on the incipient occlusal caries. Study design: In our study, 100 permanent molar teeth, which were considered to have incipient, enamel caries (D1 and D2 threshold values) according to ICDAS II score. After the visual examination, caries measurements have been applied to all teeth by using DIAGNOdent pen (DP), CarieScan PRO (CP) and SoproLife camera (SC). In addition, in vitro examinations were repeated 2 weeks later. After sectioning and evaluation in stereomicroscope, the lesion depth was determined with histological criteria that are accepted for the gold standard for this research. Sensitivity, specificity, accuracy and area under the ROC curve were calculated at D1 and D2 thresholds. The infra-examiners' reproducibility were analysed using Cohen 's kappa statistics and intraclass correlation coefficient (ICC). Results: Infra-examiner repeatability values varied from 0.94 to 0.99 and kappa values ranged from 0.90 to 0.99. While the highest sensitivity and specificity value showed for SC at D1 and D2 thresholds, CP presented the lowest values. The area under ROC curves (Az) varied from 0.70 to 0.99. ICDAS II showed the highest area under ROC curves (Az). Conclusions: ICDAS II, visual diagnostic method by itself is considered to sufficient in order to diagnose incipient occlusal caries. SC may be used as an alternative method for the ICDASII, since its advantages by displaying caries lesion on the computer monitor, follow-up and motivation of the patients provided.

WOS: 000400956500004, PubMed ID: 30894999, Background/purpose: Nowadays, laser systems play crucial roles in endodontic treatments. Therefore, these systems should be investigated in terms of parameters that may prevent periodontal tissues damages during laser irradiation. In this context, the purpose of this study was to evaluate temperature rises during the application of different power levels of potassium titanyl phosphate (KTP) and neodymium-doped:yttrium aluminum garnet (Nd:YAG) lasers to external primary root canals. Materials and methods: Sixty primary mandibular molars were selected and chemomechanical preparation was performed. KTP laser treatment was applied to 30 of these 60 samples and the remaining 30 received Nd:YAG laser treatment. The teeth samples received laser application (KTP or Nd:YAG) at three different power levels (1 W, 1.5 W, and 2 W, respectively, applied to 10 samples from each group). Nine holes were drilled (1 mm in diameter) through the level of the coronal, middle, and apical third of each tooth canal to provide entry for a Type L thermocouple wire, which was used to measure temperature changes. Data were assessed with two-way analysis of variance and the Tukey test. Results: All power levels indicated statistically significant differences between Nd:YAG and KTP laser systems (P < 0.05). Moreover, the same regional (apical, middle, and coronal) comparisons performed between Nd:YAG and KTP laser systems showed statistically significant differences (P < 0.05). Conclusion: All parameters of KTP laser indicated lower temperature rises than Nd:YAG laser. Therefore, KTP laser may be preferable to protect the periodontal tissues from harmful thermal effects during the endodontic treatment of primary root canals. Copyright (C) 2016, Association for Dental Sciences of the Republic of China. Published by Elsevier Taiwan LLC.

WOS: 000333442400004, PubMed ID: 24492107, The present study aimed to compare post-aging microtensile values of fissure sealant(FS) containing amorphous calcium phosphate(ACP) with or without bonding after various enamel-etching methods. The buccal enamel surfaces of teeth were prepared and divided into five main group according to enamel etching (Group 1; acid-etching, Group 2; air-abrasion, Group 3; 2W, Group 4; 3W, and Group 5; 4W of Er:YAG laser). Each main group was subdivided as with(Subgroup B) or without(Subgroup A) a bonding system. We applied FS-containing ACP to etched enamel surfaces. All specimens were aged by Thermocycling and water bath. We then measured microtensile bond strengths and analyzed data with two-way ANOVA and Tukey's tests. We found a statistically significant difference between Group 1 and Group 2, between Subgroup B of Group 5 and Subgroups B of all other groups, and between Subgroups A and Subgroups B of all main groups (p

WOS: 000318553400003, PubMed ID: 23480272, Objective: The present study investigated the effects of the Er:YAG laser's different pulse repetition rates on temperature rise under various primary dentin thicknesses. Background data: The Er:YAG laser can be used for restorative approaches in clinics and is used to treat dental caries. There are some reports that explain the temperature rise effect of the Er:YAG laser. Recently, the Er:YAG laser has been found to play an important role in temperature rises during the application on dentin. Methods: Caries-free primary mandibular molars were prepared to obtain dentin discs with 0.5, 1, 1.5, and 2 mm thicknesses (n = 10). These discs were placed between the Teflon mold cylinders of a temperature test apparatus. We preferred three pulse repetition rates of 10, 15, and 20 Hz with an energy density of 12.7 J/cm(2) and a 230 mu s pulse duration. All dentin discs were irradiated for 30 sec by the Er:YAG laser. Temperature rises were recorded using an L-type thermocouple and universal data loggers/scanners (E-680, Elimko Co., Turkey). Data were analyzed by two-way ANOVA and Tukey tests. Results: Whereas the lowest temperature rise (0.44 +/- 0.09 degrees C) was measured from a 10 Hz pulse repetition rate at a dentin thickness of 2 mm, the highest temperature rise (3.86 +/- 0.43 degrees C) was measured from a 20 Hz pulse repetition rate at a 0.5 mm dentin thickness. Conclusions: Temperature rise did not reach critical value for pulpal injury in any primary dentin thicknesses irradiated by a high repetition rate of the Er:YAG laser.