İstanbul Galata Üniversitesi Kurumsal Akademik Arşivi
DSpace@Galata, İstanbul Galata 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 telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Color matching and metameric behavior of composite resins applied on anodized titanium surfaces: an in vitro spectrophotometric study
(2026) Davut, Umur; Özyılmaz, Özge Doğanay; Özyılmaz, Özgün Yusuf
Background The aim of this study was to evaluate the color matching and metameric behavior of two different composite resins applied to titanium surfaces anodized to yellow and pink colors. The study aimed to determine the effects of anodization color and composite resin type on color performance in hybrid prosthesis and screw access hole closure applications. Materials and methods A total of 72 Grade 5 titanium discs (10 mm diameter × 2 mm thickness) were allocated to three anodization conditions: nonanodized/gray (0 V, n = 24), yellow (55 V, n = 24), and pink (80 V, n = 24). Each anodization group was subdivided into two subgroups: 3 M Filtek Z250 (microhybrid) and Tokuyama Estelite Sigma Quick (supra-nano hybrid) composite resins (A2 shade, 2 mm thickness; n = 12 per subgroup). Gray titanium + composite specimens were used as the reference for ΔE₀₀ calculations; yellow and pink anodization groups constituted the experimental groups. Color measurements were performed using a spectrophotometer (Konica Minolta CM-3700 A) under four light sources (D65, D50, incandescent A, and F11). Data were analyzed using mixed-design repeated-measures ANOVA, Bonferroni post hoc test, and independent samples t-test (α = 0.05). Results Anodization color (η² = 0.941) and composite type (η² = 0.952) demonstrated strong effects on ΔE₀₀ values (both p < 0.001). Light source showed statistically significant but clinically negligible effect (η² = 0.521, mean difference < 0.1 ΔE₀₀). Pink anodization exhibited higher color differences than yellow (2.84–2.99 vs. 1.53–1.62), and Tokuyama composite higher than 3 M (2.89–3.12 vs. 1.41–1.54) (both p < 0.001). Yellow+3 M combination showed lowest values (0.91–0.97), while Pink+Tokuyama showed highest (3.68–3.97). Metamerism index remained minimal (MI < 0.21). Conclusions Careful material selection is essential for optimal esthetics in anodized titanium-composite systems. Yellow anodization combined with a microhybrid composite demonstrated the most favorable color matching performance under
Influence of Thermal Aging on the Marginal/Internal Fit of Incisor Veneered and Monolithic Zirconia Crowns
(Wiley, 2026) Özkurt Kayahan, Zeynep; Özden, Yunus Emre; Çelikyürek Karabağlı, Zeynep; Özyılmaz, Özgün Yusuf; Özer, Füsun; Blatz, Markus B.
Objectives: The aim of the study was to evaluate and compare the effect of thermal aging on the marginal and internal adaptation of veneered and monolithic zirconia (MZ) crowns. Materials and Methods: A maxillary central incisor abutment was digitally designed, fabricated using resin, and scanned for crown design. MZ (IPS e.max ZirCAD Prime Esthetic) and veneered zirconia (VZ; coping: Everest, KaVo; layering: IPS e.max Ceram) crowns were fabricated (n=10). STL files were analyzed in Geomagic Design X to calculate root mean square (RMS) values within the selected marginal and internal regions before and after 10,000, 30,000, and 50,000 thermal cycles with superimposition. Data were analyzed using Shapiro–Wilk and Mann–Whitney U tests. The comparison of thermal aging treatments was evaluated using the Friedman and post hoc Wilcoxon signed-rank tests (p<0.05). Results: Significant differences were found between MZ and VZ crowns (p<0.05). In the MZ group, marginal gaps increased from 104μm (T0) to 115μm (T3), and internal gaps from 122μm (T0) to 146μm (T3). In the VZ group, marginal gaps increased from 82μm (T0) to 128μm (T3) and internal gaps from 136μm (T0) to 204μm (T3). VZ crowns showed higher dimensional changes than MZ crowns. Conclusions: Thermal cycling significantly affected the fit of zirconia crowns. VZ crowns exhibited greater dimensional changes after 30,000 and 50,000 thermal cycles, while MZ crowns maintained superior marginal fit during the same periods. Clinical Significance: This study highlights the influence of thermal aging on the marginal and internal adaptation of veneered and MZ crowns. VZ may be more susceptible to marginal or internal discrepancies after thermal aging, when compared with the MZ.
Knowledge and Attitudes of Dental Patients Toward Botulinum Toxin Treatment
(2025) Dede, Merve; Özyetim, Esra Bilgi
Background: This study aims to evaluate the knowledge, attitudes, and perceptions of patients applying to a dental faculty for treatment regarding botulinum toxin. Methods: The study was conducted at the İstanbul Yeni Yüzyıl University Faculty of Dentistry Hospital and included a total of 139 patients. A 3-section questionnaire was used: (1) demo?graphic data, (2) knowledge of Botox, and (3) attitudes toward Botox applications. The data were analyzed using IBM SPSS 23.0, and the Kruskal-Wallis test, Dunn’s test, Mann-Whitney U test, Chi-square test, and Fisher’s Exact tests were applied. Results: Among the participants, 67.6% were female, 32.4% were male, and 70.6% were between 18 and 44 years old. Only 15.1% of the participants correctly answered the ques?tion “What Is Botox?.” While 75.5% of the participants stated that Botox is used for cosmetic purposes, their knowledge of its therapeutic applications was limited. Additionally, 20.9% of participants reported being aware of the side effects of Botox, while 33.1% stated that they had considered undergoing Botox treatment. 12.9% of the participants had previously undergone Botox procedures, with 72.2% receiving it for aesthetic reasons and 27.8% for medical purposes. Conclusion: The results of the study indicate that patients have insufficient knowledge regarding the therapeutic uses of botulinum toxin. Participants predominantly perceive Botox as a cos?metic procedure and have limited awareness of its medical benefits. Furthermore, a significant portion of participants believe that Botox procedures can only be performed by plastic surgeons and dermatologists, demonstrating low awareness of the competency of dentists in administer?ing such treatments. This study highlights the need to increase patient awareness regarding both the aesthetic and therapeutic uses of Boto
Anatomical Relationship of the Mylohyoid Ridge, Lingual Concavity, and Mandibular Canal: A Retrospective CBCT Study
(MDPI, 2023) Şen, Selva; Girit, Melike Nur; Ansen, Gamze; Pençe, Kadriye Betül; Yüzbaşıoğlu, Neslihan
This study aimed to determine the position of the mylohyoid ridge (MR) and lingual concavity (LC) in the mandible and their relationship with the mandibular canal (MC) and submandibular fossa, to provide anatomical guidance for surgical procedures in this region. Methods: A retrospective analysis was performed on cone beam computed tomography (CBCT) scans from 200 adult patients who had undergone imaging for dental treatment. On cross-sectional images at the level between the first and second molar roots, the following measurements were obtained: LC horizontal depth, LC height, LC depth, MR height, MR depth, and the distances from MR to MC (MR–MC) and LC to MC (LC–MC). Results: Mean values were: LC horizontal depth: 3.72 ± 0.90 mm, LC height: 11.74 ± 2.01 mm, LC depth: 12.54 ± 3.03 mm, MR height: 17.66 ± 2.60 mm, MR depth: 6.87 ± 2.38 mm, MR-MC: 8.30 ± 2.00 mm, and LC-MC: 3.72 ± 0.87 mm. All parameters were symmetrical between the right and left sides of the mandible, with no significant sex differences. The positions of the MR and LC were related to each other, and the position of the MC was related to the positions of the LC and MR. There was no correlation between the horizontal depth of the LC and the position of the MR, LC and MC. Conclusions: The vertical positions of the MR and LC are related to each other and MC. Therefore, it can be used as a landmark in implant surgery.
Automated deep learning detection of orthodontically induced external apical root resorption in maxillary incisors on panoramic radiographs
(2026) Özden, Samet; Kula, Betül; Tankuş, Mahmut
Objectives This study aimed to develop and compare two YOLOv12-based deep learning models—object detection and pose estimation—for the automatic classification of orthodontically induced external apical root resorption (OIEARR) using panoramic radiographs. Materials and methods A total of 624 panoramic radiographs obtained from 312 patients aged 10–18 who underwent at least 12 months of fixed orthodontic treatment were retrospectively analyzed. Each maxillary central and lateral incisor was graded for OIEARR severity on a 4-point scale (Grade 0 to Grade 3) by two experienced orthodontists serving as the ground truth. Two YOLOv12-based models were trained: an object detection (OD) model for regional analysis and a pose estimation (PE) model for anatomical landmark localization. Both models were trained and validated on annotated panoramic images and evaluated using accuracy, precision, recall, specificity, F1-score, confusion matrix, and ROC-AUC. Results The PE model outperformed the OD model across all evaluation metrics, demonstrating superior performance in detecting OIEARR. Specifically, the PE model achieved a weighted F1-score of 0.88, compared to 0.60 for the OD model. It also showed higher accuracy (0.93 vs. 0.78), precision (0.88 vs. 0.64), and recall (0.88 vs. 0.59), confirming its robustness in root resorption classification. Particularly in Grade 1 and Grade 2 resorption categories, the PE model demonstrated markedly superior classification performance (F1=0.85 and 0.88, respectively), while maintaining excellent detection in Grade 3 cases (F1=0.95). Confusion matrix analysis revealed that most misclassifications occurred between neighboring grades. ROC-AUC values for the PE model were consistently high (0.90–0.99), indicating strong discriminative ability across all resorption stages. Conclusions The YOLOv12x PE model offers a reliable and sensitive tool for detecting varying degrees of root resorption on panoramic radiographs. Its fine-grained anatomical localization capabilities provide an advantage for early diagnosis, making it a promising approach for clinical decision support in orthodontics.
