İstanbul Sağlık ve Teknoloji Üniversitesi Kurumsal Akademik Arşivi
DSpace@İSTÜN, Üniversite mensupları 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
Post-processing protocols in 3d printed dental restorations: A literature-based data analysis
(Dennis Barber Journals, 2025) Mert, Selen Elif; Özkan, Yiğit Alp; Olkun, Abdullah Yaşar; Dilaverler Yardım, Esra Ayşe
Objectives: This literature-based data analysis aims to evaluate the effects of post-processing protocols on the physical, mechanical, and surface properties of dental restorations produced using 3D printing technologies (SLA, DLP, and LCD systems). The objective is to highlight the variability in current approaches and thematically analyze the clinical implications of these differences. Materials-methods: A systematic search of the literature published between 2018 and 2025 was conducted using PubMed, Scopus, and Web of Science databases, in accordance with PRISMA guidelines. Inclusion criteria were: (1) studies involving 3D printed resins, (2) evaluation of at least one post-processing variable (e.g., curing, cleaning, or support removal), and (3) focus on definitive or interim prosthodontic restorations. Studies involving orthodontic models, aligners, or CAD/CAM-milled restorations were excluded. The included studies were categorized into three groups: curing protocols, cleaning procedures, and support structure removal. Due to methodological heterogeneity, no meta-analysis was performed; instead, findings were interpreted through a descriptive, literature-based data analysis approach. RESULTS: A total of approximately 320 unique studies were identified through prior systematic and narrative reviews. After applying predefined inclusion criteria, 12 studies were selected for in-depth evaluation in this literature review. Although some included studies were systematic reviews and meta-analyses, this study did not perform an independent meta-analysis. Variations in curing time, light intensity, and atmospheric conditions were found to affect degree of conversion, microhardness, and flexural strength. Cleaning protocols involving different solvents and application techniques influenced surface roughness and dimensional accuracy. The support removal process impacted marginal adaptation, surface integrity, and gloss retention. Despite methodological differences, the overall evidence indicates that post-processing parameters significantly influence clinical performance outcomes. Conclusion: This analysis demonstrates that post processing protocols significantly affect material quality and clinical applicability. The findings underscore the need for manufacturer-independent, standardized protocols to ensure predictable outcomes in 3D printed dental restorations.
Weibull characteristics and modulus calculation in adhesion studies: A methodological investigation
(Dennis Barber Journals, 2025) Berisha, Florentin; Şener, Alpaslan; Cankja, Angelo; Uzun Pekintürk, Berre; Freitas Brum Souza, Luiza; Özcan, Mutlu
Objective: This study aimed to determine the minimum number of specimens required to obtain statistically reliable conclusions in adhesion studies using the Weibull statistic and to estimate the probability of failure under defined conditions. Materials-methods: Specimens (N=160) were prepared from resin composite (RC: Brilliant, Coltene), lithium disilicate (LD: IPS e.max Press, Ivoclar), zirconia (YZ: Z-CAD, Metoxid AG), and titanium (TI: Ti CP Grade 4, Permascand). RC, YZ, and TI were air-abraded (50 µm Al2 O2 , 2.5 bar, 10 s), and LD was etched with 5% hydrofluoric acid (20 s). Resin cement cylinders (Ø=3×4 mm) were bonded using one of the following: Variolink Esthetic DC (Ivoclar), Panavia V5 (Kuraray Noritake), Panavia 21 (Kuraray Noritake), or Multilink Automix (Ivoclar). The combinations tested were as follows: RC-Variolink Esthetic DC/Panavia V5; LD-Variolink Esthetic DC/Panavia V5; YZ-Panavia 21/Multilink Automix; TI Panavia 21/Multilink Automix. Half of the specimens were stored at 37 °C for 24 h; the other half underwent thermocycling (x6000, 5-55 °C). Shear bond strength was tested (1 mm/min), and failure modes were assessed under digital microscopy. Weibull analysis evaluated bond reliability for 10, 20, 30 and 40 specimens in each group. Maximum likelihood estimation and 95% confidence intervals determined differences. Results: For RC, Variolink Esthetic DC showed higher characteristic strength (η) at n=10 and 20 vs. n=30 and 40. Panavia V5 showed a significant decrease from n=10 to 40 only in the non-aged condition. In LD, both cements showed decreasing η with increasing n. In YZ and TI, both Panavia 21 and Multilink Automix showed reduced characteristic strength with increasing n. Failures were mainly cohesive in LD but adhesive with the other materials. Conclusions: Increasing sample size reduced characteristic strength (η) across all materials, indicating that small sample sizes overestimate adhesive performance. Larger samples yield more reliable estimates. The Weibull modulus (β) remained stable or increased slightly after aging, especially for zirconia.
Prosthetic rehabilitation of a large maxillary defect due to nasopharyngeal tumor resection: A case report
(Dennis Barber Journals, 2025) Topuz, Buğra Tuğ; Kasıl, Ece; Ayvalıoğlu Şamiloğlu, Demet Çağıl
Introduction: Nasopharyngeal tumors are malignant neoplasms located in the epithelial lining of the nasopharynx, and they often require aggressive treatment modalities including surgery, radiotherapy, and/or chemotherapy. Surgical resection of these tumors, especially when involving adjacent maxillary and palatal structures, frequently results in large maxillofacial defects. This case report presents the comprehensive prosthetic rehabilitation of a patient with a large acquired maxillary defect following surgical resection of a nasopharyngeal tumor. Case Description: A 49 years old male patient with a large maxillary defect resulting from extensive surgical nasopharyngeal tumor resection applied to the clinic of Department of Prosthodontics. Following surgery, the patient had received postoperative radiotherapy and chemotheraphy. Prior to definitive prosthetic rehabilitation, endodontic and periodontal treatments of the remaining teeth were completed. Support was taken from the remaining teeth (16-15, 12-11-21- 22) to fabricate a precision attachment-retained obturator that provided partial separation between the oral and nasal cavities. A quadrilateral design was performed. For the mandibular partial edentulism, a precision attachment-retained, metal framework removable partial denture was designed. Results: The patient’s issues with speech and nutrition deficiency were resolved with the obturator prosthesis and the esthetic demands were fullfilled. Conclusion: Within the scope of this case, the use of an obturator provided functional and esthetic rehabilitation of a patient with a large maxillary defect following oncologic surgery.
Prosthetic approach to tooth structure damage associated with dietary habits and bruxism: A case report
(Dennis Barber Journals, 2025) Özkan Dayıoğlu, Selin; Ayvalıoğlu Şamiloğlu, Demet Çağıl; Rastgar Safari, Mahya
Introduction: Tooth structure loss resulting from parafunctional habits such as bruxism, compounded by erosive dietary factors, presents a multifactorial challenge in restorative dentistry. Patients often exhibit a combination of advanced anterior wear, dentin hypersensitivity, and non carious cervical lesions. Successful rehabilitation requires a minimally invasive, esthetically driven, and functionally stable prosthetic approach. This case presents a comprehensive adhesive and occlusal strategy for managing tooth wear caused by bothbruxism and dietary habits. Case Description: A 54-year-old female patient presented with severe anterior tooth wear, dentin hypersensitivity, and non carious cervical lesions attributed to parafunctional habits, particularly bruxism. The maxillary central incisors exhibited significant structural compromise and esthetic concerns. To fulfill the functional and esthetic needs of the patient, lithium disilicate crowns were placed on the maxillary central incisors. Additionally, seven maxillary anterior teeth were restored using minimally invasive lithium disilicate laminate veneers. A monolithic zirconia crown was placed on the maxillary first molar to reinforce posterior occlusal support. Tooth preparations followed adhesive principles, and the occlusion was carefully evaluated and adjusted. A protective occlusal splint was delivered post-treatment to eliminate future damage. Discussion: This case emphasizes the importance of early diagnosis and a comprehensive, adhesive-based prosthodontic treatment plan in managing bruxism induced tooth wear. Lithium disilicate ceramics allowed for both conservative tooth preparation and high esthetic outcomes. The use of a monolithic zirconia crown in the posterior ensured durability. The integration of occlusal assessment and an occlusal splint served as critical components for maintaining long-term stability. Conclusion: Through a customized, adhesive prosthodontic strategy, it was possible to restore esthetics, relieve sensitivity, and prevent further damage in a patient affected by bruxism.
Photogrammetry-assisted digital workflow for full-arch monolithic zirconia restorations: A clinical report
(Dennis Barber Journals, 2025) Güler, Edanur; Sabancı, Nibal; Dilaverler Yardım, Esra Ayşe
Introduction: Achieving cross-arch accuracy and passive fit remains a major challenge in conventional impression techniques for full-arch implant restorations. In contrast, photogrammetry-assisted digital workflows offer enhanced precision, efficiency, and predictability. This clinical report describes the rehabilitation of a 56-year-old fully edentulous female patient using a fully digital protocol and monolithic zirconia prostheses for both jaws. Case Description: Twelve endosseous implants (Ø3.7 mm, length 10–12 mm; ETK, France) were placed in anterior and posterior regions of the maxilla and mandible. After successful osseointegration, multi-unit abutments were connected. Final impressions were obtained using a hybrid protocol that combined photogrammetry (Imetric-Icam, Switzerland) with intraoral scanning (iTero Lumina, USA). With reference bars in place, interocclusal records and vertical dimension were registered using C-type vinyl siloxane ether (Zetaplus, Zhermack, Italy). Facial photographs and marker data were recorded in natural head position and transferred to the laboratory. Digital alignment and virtual articulation (Artex, Germany) were performed. A CAD-CAM resin mock-up (Armaresin, Turkey) was fabricated and evaluated intraorally for esthetics and occlusion. Final restorations were designed as full-arch, screw-retained prostheses using monolithic zirconia (Ceramill Zolid FX, Amann Girrbach, Austria) and torqued to 15 Ncm. Discussion: The photogrammetry-based workflow demonstrated superior cross-arch accuracy and passive fit compared to conventional techniques. The try-in allowed for verification of occlusal harmony, vertical dimension, and esthetics in a single appointment. Follow-up at 1-, 3-, 6-month, and 1-year intervals revealed no peri-implant complications. The patient reported high satisfaction in function and esthetics. This case highlights the clinical advantages of photogrammetry and monolithic zirconia in streamlining full-arch implant rehabilitation.
