Yazar "Sahin, Onur" seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • [ X ]
    Öğe
    COMPARISON OF SUBJECTIVE ESTHETIC PERCEPTIONS OF DENTISTS WITH DIFFERENT GENDER AND CLINICAL EXPERIENCES WITH OBJECTIVE DENTOLABIAL ESTHETIC MEASUREMENTS
    (Cumhuriyet University Faculty of Dentistry, 2020) Geduk, §ükriye Ece; Sahin, Onur; Velioglu, Neslin
    Objective: This study aimed to evaluate the consistency of specific measurable dentolabial criteria between the esthetic values accepted in the literature and the subjective opinions of physicians. Materials and Methods: Four associate professors and four research assistants in the field of prosthodontics were selected as the examiners in the study. Photographs of smiles (focusing on the mouth region of the face) taken from 200 volunteers were examined. The results of the objective measurements of the curvature of the incisal edge and lower lip parallelism, the incisal edge and lower lip contact, the laugh line, the buccal corridor and the interincisal line and midline variables, and the subjective assessments of the evaluators were compared using Cochran’s Q test. Results: Esthetic perception is subjective; however, there was a significant correlation between the objective measurements and subjective perceptions in the incisal edge and lower lip parallelism, laugh line, and buccal corridor variables. No statistically significant difference was found between the objective computer measurements and the evaluations of the male and female examiners or between the perceptions of the specialists (associate professors) and the research assistants. Conclusion: There is no consensus between esthetically objective findings and subjective perceptions. © 2020. All rights reserved.
  • [ X ]
    Öğe
    Effect of simulated tootbrushing on surface roughness of sealant agent coupled nanohybrid composite resins
    (Wiley, 2022) Halis, Gizem; Koroglu, Aysegul; Sahin, Onur; Dede, Dogu Omur; Yilmaz, Burak
    Objective To investigate the effect of toothbrushing on the surface roughness (R-a) of different sealant agent coupled nanohybrid composite resins. Materials and Methods One hundred sixty disc-shaped (10 x 2 mm) specimens were prepared from four different nanohybrid composite resins (Z-550, Tetric EvoCeram, Clearfill Majesty, Ice). Specimen groups were divided into four subgroups for conventional polishing (control) and to apply three different surface sealant agents (Palaseal, Optiglaze, Biscover LV) (n = 10). The R-a values of the specimens were recorded before (R(a)0) and after 10,000 cycles of toothbrushing (R(a)1). The surface properties of the specimens were evaluated with scanning electron microscope (SEM). Data were statistically analyzed by two-way analysis of variance (ANOVA), Tukey HSD, and paired sample t tests. Results Composite resin material, surface treatment, and their interaction were significant on R-a values (p < 0.001). Significant decrease in R(a)0 values observed for surface sealant agent coupled Clearfill Majesty and Tetric EvoCeram composite resin groups compared with the control groups (p < 0.05). After simulated one-year toothbrushing, the control group of Clearfill Majesty had the highest R(a)1 value (p < 0.001). The R(a)1 values of all groups were significantly higher than the R(a)0 values (p < 0.05). Conclusions Simulated 1-year toothbrushing increased the surface roughness of all nanohybrid composite resin materials. Optiglaze and Biscover LV sealant agents on Tetric EvoCeram, and all tested sealant agents on Clearfill Majesty enabled smoother surfaces than conventional polishing after toothbrushing. Clinical Significance Because toothbrushing increases the surface roughness of tested nanohybrid composite resins, the application of surface sealant agents on some of the tested resins can be considered for smoother surfaces.
  • [ X ]
    Öğe
    The Effect of the Toothbrushing and Surface Treatments on the Surface Roughness of Interim Crown Materials Used for Conventional, Subtractive, and Additive Manufacturing Techniques: An in Vitro Study
    (Selcuk University, 2023) Bozoğulları, Hatice Nalan; Köro?lu, Ayşegül; Sahin, Onur; İzzetağa, Beşar
    Background: This study aimed to compare the effect of the surface treatment and toothbrushing abrasion on the surface roughness of interim crown material specimens manufactured using conventional, subtractive, and additive processing techniques. Material and methods: 80 disk-shaped specimens were prepared from 4 different interim crown materials; one auto-polymerized polymethyl methacrylate resin (PMMA);(IM) and one bis-acryl composite resin;(AC) for conventional technique, one computer-aided design/computer-aided manufacturing (CAD-CAM) PMMA block;(TC) for subtractive process, one 3-dimensionally (3D) printed resin;(CB) for additive process. Specimens of each interim crown material were divided into two subgroups according to applied surface treatments; conventional polishing or surface sealant agent coupling (n=10). The surface roughness values of specimens before (Ra0) and after 10,000 cycles of toothbrushing (Ra1) were measured with a profilometer. Data were statistically analyzed. Results: The polished groups of all interim crown materials showed significantly higher Ra0 values compared to the sealant groups before toothbrushing (p?0.05). While the polished IM groups exhibited the highest Ra0 value (0.44±0.08), the sealed TC groups exhibited the lowest Ra0 value (0.23±0.06). The Ra values of all material groups increased after simulated 1-year toothbrushing. While the polished IM group exhibited the highest Ra1 value (0.45±0.14), the sealed CB group had the lowest Ra1 value (0.31±0.09). Conclusion: It was observed that toothbrushing caused an increase in the surface roughness of all interim materials. The application of a surface sealant agent to these materials is more effective than polishing to reduce surface roughness. Sealed 3D printed resin for additive process exhibited the lowest mean roughness value after toothbrushing. © 2023, Selcuk University. All rights reserved.