Recep Tayyip Erdoğan Üniversitesi Kurumsal Akademik Arşivi
DSpace@RTEÜ, Recep Tayyip Erdoğan Üniversitesi tarafından doğrudan ve dolaylı olarak yayınlanan; kitap, makale, tez, bildiri, rapor, araştırma verisi gibi tüm akademik kaynakları uluslararası standartlarda dijital ortamda depolar, Üniversitenin akademik performansını izlemeye aracılık eder, kaynakları uzun süreli saklar ve yayınların etkisini artırmak için telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Engineering strength through microstructure: gradation and content effects in cemented high-sulfur tailings-crushed rock backfill
(Elsevier, 2026) Huang, Zhiqiang; Jiang, Meilin; Cao, Shuai; Yılmaz, Erol
This study addresses the environmental hazards posed by the extensive buildup of crushed rock and sulfur-rich tailings produced during mining operations. A complete lab study was carried out to assess strength performance and internal microstructure of a cemented fill system made from high-sulfur tailings and crushed rock (CHSTCRB). UCS trials and SEM inspections were performed based on an orthogonal experimental design. Key parameters, including UCS, critical damage value ( Dpk ), failure modes, energy dissipation behavior, and microstructural features, were examined. The findings show that UCS declines as the cement-to-tailing (c/t) ratio drops, with factor influence ranked as follows: c/t ratio having the greatest impact, followed by crushed rock gradation, and then content. Proper aggregate design notably boosts strength while easing degradation effects. The deterioration behavior is ruled by a dual effect of cement hydration and pyrite oxidation, exhibiting a distinct three-stage evolutionary process. Prolonged curing increases Dpk , progressively weakening the internal microstructure, enhancing porosity, and resulting in a marked reduction in mechanical strength. As rock content increases and particle size distribution becomes optimized, the failure mechanism transitions from a brittle, tensile-dominated fracture to a hybrid tensile–shear mode, characterized by pronounced stratification and extensive, inter-connected crack propagation. Energy evolution analysis shows a continuous rise in total energy, while elastic strain energy follows a rise–fall trend, peaking before falling as structural damage develops. In the interim, dissipated energy escalates sharply in later steps, revealing intensified damage and fracture activity. An elevated c/t share facilitated cemented materials and basic compaction formations. Extended cure periods enhanced ITZ (interfacial transition zone) contact, and rock aggregate well mitigated worsening of high-sulfur tailings. Accordingly, these findings run a solid scientific basis for optimizing design and engineering application of CHSTCRB systems in contemporary mining operations.
Comparative evaluation of dental caries and periodontal conditions and oral health-related quality of life of dental and medical students: a cross-sectional study
(BioMed Central Ltd, 2026) Huseynova, Günay; Yorgancılar, Nur; Aydoğan, Gözde Nur; Candemir, Derya Açıkgöz; Köse, Oğuz
Background: The aim of this study is to comparatively examine the dental caries and periodontal health status of dental (DS) and medical students (MS) and to evaluate their quality of life related to oral health using the Oral Health Impact Profile–14 (OHIP-14) scale. Materials and methods: The cross-sectional study included a total of 400 systemically healthy volunteers from 1st-5th year DS (n = 200) and MS (n = 200) students of Recep Tayyip Erdoğan University. Participants’ body mass index was recorded; clinical dental (decayed, missing, and filled teeth (DMFT)) and periodontal parameters (plaque index (PI), gingival index (GI), bleeding on probing index (BOP), and probing pocket depth (PPD)) were measured. Oral Health–Related Quality of Life (OHRQoL) was assessed using the OHIP-14 questionnaire. Statistical analyses were performed to compare the two faculties across all academic years (1st–5th year) and evaluate the associations between variables. Additionally, adjusted multiple linear regression analyses were conducted to determine the independent effect of academic year on oral health parameters while controlling for gender and body mass index. The significance level was set at p < 0.05. Results: In DS, the PI, GI, BOP, and PPD parameters were found to be significantly lower than in MS (p < 0.05). In intra-faculty comparisons, DS generally showed a positive trend in dental, periodontal, and OHRQoL as their class level increased, while the opposite was observed in MS. In inter-faculty comparisons at each class level, significant differences were obtained at all parameters in all classes except the first year (p < 0.05). Class level was determined to be an associated factor for all oral health parameters in students of both faculties. Conclusion: This cross-sectional study showed that, unlike DS, lower levels were observed in dental and periodontal health status and OHRQoL were observed in MS as their class level increased. In this context, including topics related to oral health awareness and daily care habits in MS curricula could be beneficial.
Investigation of the effects of two- and three-implant supported overdenture prostheses on peri-implant bone and mandibular trabecular bone using fractal analysis and radiomorphometric methods on panoramic radiographs
(BioMed Central Ltd, 2026) Özgür, Furkan; Korkmaz, Meltem Zihni; Bostan, Semih Alperen; Köse, Taha Emre
Background: To compare the average values of fractal and radiomorphometric analysis measurements in patients using overdenture prostheses supported by two or three implants. Methods: This retrospective study analyzed panoramic radiographs of 40 patients (aged 40–90 years) treated with overdentures supported by either two or three implants (n = 20 per group). Baseline and 1–2-year follow-up radiographs were evaluated. Fractal dimension was assessed in mesial, distal, and apical peri-implant regions and averaged at the patient level to avoid clustering of implant-level observations. Radiomorphometric indices, including mandibular cortical width (MCW), mandibular cortical index (MCI), panoramic mandibular index (PMI), antegonial index (AI), and gonial index (GI), were measured bilaterally. Multiple linear regression analyses were performed to determine independent predictors of fractal dimension changes (T1–T0). Results: Fractal analysis showed no significant intergroup differences in overall trabecular bone structure. A significant increase over time was observed only in distal fractal measurements in the two-implant group, with higher follow-up values compared with the three-implant group (p < 0.05). At follow-up (T1), mandibular cortical width (MCW) and antegonial index (AI) values were significantly higher in the three-implant group (p < 0.05), whereas no differences were detected for PMI or MCI. Regression analysis demonstrated that baseline fractal values were significant predictors of fractal dimension changes in all regions, whereas implant configuration was significantly associated only with distal fractal change. Conclusion: Fractal analysis showed no significant difference in overall trabecular bone adaptation between two- and three-implant–supported overdenture groups. Radiomorphometric findings suggest a potential association between implant configuration and cortical bone characteristics; however, these findings should be interpreted with caution. Regression analysis indicated that baseline fractal values were the strongest predictors of subsequent changes, while the effect of implant configuration was limited to the distal region. These findings should be interpreted cautiously and considered hypothesis-generating rather than confirmatory.
Diagnostic accuracy of AI-assisted point-of-care ultrasound for abdominal free fluid detection in FAST trauma assessment: a systematic review and meta-analysis
(BioMed Central Ltd, 2026) Çelik, Ali; Topaloğlu, Ensar; Yazıcı, Mümin Murat
Study objective: Point-of-care ultrasound (PoCUS) is widely used in trauma care through the Focused Assessment with Sonography for Trauma (FAST) protocol, but its accuracy is highly operator-dependent. Artificial intelligence (AI) may reduce variability and improve reliability. This systematic review and meta-analysis evaluated the diagnostic accuracy of AI-assisted PoCUS for detecting free fluid in trauma patients. Methods: We searched PubMed, Scopus, and Web of Science up to April 2025, following PRISMA-DTA guidelines (PROSPERO ID: CRD420250615096). Eligible studies assessed AI-assisted PoCUS using the FAST or FAST-equivalent views and provided sufficient data for diagnostic accuracy analysis. Because one eligible study evaluated an ascites cohort rather than trauma patients, we included it in the broader abdominal free-fluid analysis but excluded it from the trauma-only sensitivity analysis. Pooled estimates were calculated with a bivariate random-effects model. Study quality was assessed using QUADAS-AI tool. Results: Seven retrospective studies (n = 2,332 patients, >34,000 images/videos) were included. The pooled analyses were based on the diagnostic units reported by the original studies, which varied across image-, frame-, video/clip-, FAST-view-, and examination-level data. In the trauma-only analysis, pooled sensitivity for detecting abdominal free fluid was 91.1% (95% CI: 77.9–96.8%) and specificity was 97.5% (95% CI: 95.3–98.7%), with negligible heterogeneity (I² < 1.0) and an AUC of 0.98. In the broader abdominal free-fluid analysis, which included one non-trauma ascites cohort, pooled sensitivity was 91.4% (95% CI: 81.6–96.3%) and specificity was 96.8% (95% CI: 86.5–99.3%), with an AUC of 0.97. CNN-based models showed similar performance (sensitivity 92.2%, specificity 95.4%, AUC 0.97). Narrative review highlighted substantial variability across models: high-performing frameworks such as YOLOv3 and ResNet50-V2 demonstrated sensitivities of 0.90–0.99, whereas others (e.g., VGG11_bn, MaskRCNN) were markedly less accurate. Evidence for pericardial effusion detection was limited to a single retrospective study and should be interpreted cautiously. No dedicated pelvic-view diagnostic accuracy data were available. Conclusion: AI-assisted PoCUS shows promising retrospective diagnostic performance for detecting abdominal free fluid during FAST assessment in trauma settings. The strongest evidence currently supports abdominal applications, whereas data for the cardiac/pericardial component of the FAST examination remain insufficient. Prospective multicenter studies with real-time workflow integration are needed before routine clinical implementation can be recommended.
The effect of anti-tumor necrosis factor-alpha and nonsurgical periodontal therapy in individuals with rheumatoid arthritis
(BioMed Central Ltd, 2026) Yemenoğlu, Hatice; Beder, Melek; Cüre, Osman; Köse, Oğuz; Arpa, Medeni; Atak, Mehtap; Bostan, Semih Alperen
Background: TNF-α inhibitors (anti-TNF-α) decrease the amount of inflammatory cells, osteoclast formation, and bone loss. The purpose of this study was to investigate the effect of non-surgical periodontal therapy (NSPT) combined with anti-TNF-α on oxidative stress in individuals with RA and periodontitis. Methods: A total of 42 patients with RA and periodontitis who were treated with anti-TNF-α (n = 21) and not treated with anti-TNF-α (n = 21) were included in the study. Plaque index (PI), bleeding on probing (BOP), gingival index (GI), clinical attachment loss (CAL), and probing pocket depth (PPD) measurements were measured at baseline, at 3 months, and at 6 months after NSPT, and serum and gingival crevicular fluid (GCF) samples were obtained from the patients. RANKL/OPG, MMP-8, MDA, GSH, and OSI levels were evaluated using ELISA. Results: In both groups, baseline PI, BOP, GI, PPD, and CAL decreased significantly after NSPT (p < 0.05). The GCF RANKL/OPG ratio was statistically significantly lower in anti-TNF-α treated patients at baseline and at 6 months post-NSPT (p < 0.05), and the serum OSI was significantly higher in anti-TNF-α treated patients at baseline (p < 0.05). GCF MMP-8 increased significantly after NSPT in both groups compared with baseline (p < 0.05). In those treated with anti-TNF-α, OSI and MDA decreased significantly after NSPT (p < 0.05). Conclusions: The data from this study suggest that anti-TNF-α therapy can suppress inflammation and alveolar bone resorption by affecting the RANKL/OPG ratio, MMP-8, and oxidative stress parameters, and thus increase the effectiveness of NSPT.
