Background: The study investigates newly developed composite materials with advanced filler technology and modified resin matrices, designed to enhance esthetic quality, clinical efficiency, and mechanical properties. This study evaluated the effect of two light-curing protocols—a conventional low-voltage (LV) protocol (10 s at 1200 mW/cm2) and a high-voltage (HV) protocol (3 s at 3000 mW/cm2)—on the microhardness (MH), bottom/top MH ratio, and the correlation between filler content (wt%, vol%) and MH of bulk-fill resin-based composites (RBCs). Four RBCs were tested: Tetric PlusFill (TPF), Tetric Plus Flow(TPFW), Tetric PowerFill (PFL), and Tetric PowerFlow (PFW). Materials and Methods: Samples were fabricated in the laboratory using specially designed cylindrical molds (diameter = 8 mm, height = 4 mm). Initial MH was measured on the top and bottom surfaces of composite specimens 24 h after light curing using a digital microhardness tester (QNESS 60 M EVO, ATM Qness GmbH, Mammelzen, Germany). The correlation between the filler content (wt%, vol%) and the MH of the RBCs was tested. For the calculation of depth-dependent curing effectiveness, the bottom/top ratio for initial MH was used. Conclusions: The MH of bulk-fill RBCs was found to be influenced by both material composition and the applied light-curing protocol. An increase in filler content resulted in higher MH values under both protocols, with the filler volume fraction exhibiting a stronger correlation than the weight fraction. While both flowable and sculptable Tetric Plus composites exhibited higher MH values under the HV protocol, Tetric Power composites demonstrated greater initial hardness under LV protocol. The flowable composite PFW showed the most pronounced reduction in MH under HV curing. The bottom/top MH ratio exceeded 80% in all tested materials, confirming adequate polymerization throughout the composite layers.
Introduction: The main purpose of root canal filling materials is to provide an apical sealing that prevents the movement of bacteria and the diffusion of their metabolic products from the root canal system to periapical tissue. The aim of this study was to evaluate the apical sealing ability of mineral trioxide aggregate’s (MTA), epoxy resin, and zinc oxide eugenol- based sealer with single cone obturation techniques using the dye extraction leakage method. Methods: Seventy-five extracted human single-rooted teeth were instrumented using the crown-down technique with the Mtwo rotary file system to file 25/6. The teeth were randomly divided into five experimental groups (n = 15); Group 1 obturated with AH plus, Group 2 obturated with MTA BIOSEAL, Group 3 obturated with Endoseal, Group 4 positive control (POS CTRL) root canals are processed but not obturated, and negative control- apex of teeth completely covered with nail varnish, canals are not treated or obturated. In the first three groups, the single cone obturation technique with gutta-percha 25/6 was used. Apical microleakage was assessed with the dye extraction method, where the absorbance of 2% methylene blue was measured using a spectrophotometer. Results: The mean dye concentration values were MTA 22.79, AH plus 31.16, Endoseal 36.67, POS CTRL 280.15, negative control 9.01. Analysis of variance and pairwise comparisons indicated a significant difference in apical microleakage between the investigated groups (F = 3448, p < 0.001). The MTA BIOSEAL showed significantly less apical microleakage than the AH plus and Endoseal. The AH plus showed less apical microleakage than the Endoseal, although there was no significant difference between these two sealers. Conclusion: With the limitation of the study, it was concluded that MTA sealers show statistically less apical leakage than AH Plus and Endoseal.
Introduction: Diabetes is progressive condition which requires various ways of treatment. Adequate therapy prescribed in the right time helps patient to postpone development of complications. Adherence to complicated therapy is challenge for both patients and HCPs and is subject of research in many disciplines. Improvement in communication between HCP and patients is very important in patient’s adherence to therapy. Aim: Aim of this research was to explore validity and reliability of modified SERVQUAL instrument in attempt to explore ways of motivating diabetic patient to accept prescribed insulin therapy. Material and Methods: We used modified SERVQUAL questionnaire as instrument in the research. It was necessary to check validity and reliability of the new modified instrument. Results: Results show that modified Servqual instrument has excellent reliability (α=0.908), so we could say that it measures precisely Expectations, Perceptions and Motivation at patients. Factor analysis (EFA method) with Varimax rotation extracted 4 factors which together explain 52.902% variance of the results on this subscale. Bifactorial solution could be seen on Scree-plot diagram (break at second factor). Conclusion: Results in this research show that modified Servqual instrument which is created in order to measure expectations and perceptions of the patients is valid and reliable. Reliability and validity are proven indeed in additional dimension which was created originally for this research - motivation to accept insulin therapy.
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