Dokument: Influence of straight versus angulated screw channel titanium bases on failure loads of two-piece ceramic and titanium implants restored with screw-retained monolithic crowns
Titel: | Influence of straight versus angulated screw channel titanium bases on failure loads of two-piece ceramic and titanium implants restored with screw-retained monolithic crowns | |||||||
URL für Lesezeichen: | https://docserv.uni-duesseldorf.de/servlets/DocumentServlet?id=70169 | |||||||
URN (NBN): | urn:nbn:de:hbz:061-20250717-121211-7 | |||||||
Kollektion: | Dissertationen | |||||||
Sprache: | Englisch | |||||||
Dokumententyp: | Wissenschaftliche Abschlussarbeiten » Dissertation | |||||||
Medientyp: | Text | |||||||
Autor: | Helal, Edriz [Autor] | |||||||
Dateien: |
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Beitragende: | Gierthmühlen, Petra C. [Gutachter] Prof.Dr. Wilmes, Benedict [Gutachter] | |||||||
Dewey Dezimal-Klassifikation: | 600 Technik, Medizin, angewandte Wissenschaften » 610 Medizin und Gesundheit | |||||||
Beschreibung: | This dissertation investigates the influence of straight versus angled titanium bases on
the failure loads and bending moments of two-piece ceramic and titanium implants restored with monolithic zirconia crowns. The objective of this study was to evaluate the effect of abutment design on the stability of these implant systems following thermomechanical loading. In the study, 32 monolithic screw-retained zirconia crowns were categorized into four groups: two groups were mounted on titanium-zirconium implants (Ti-Zr), and two groups were mounted on ceramic implants (CI). The implants had identical dimensions (4.1 x 12 mm) but featured different abutments, which were configured either as straight (Ti-Zr-0/CI-0) or angled (Ti-Zr-25/CI-25). All samples were subjected to dynamic loading comprising 1.2 million cycles at 49 N and 1.6 Hz, as well as thermal cycling across a temperature range of 5°C to 55°C. Following these stress tests, the specimens were loaded to failure using a universal testing machine to calculate bending moments. Fracture surface analysis was performed using light microscopy and scanning electron microscopy (SEM) to determine the fracture characteristics. Statistical evaluation was conducted using ANOVA and Mann-Whitney U-tests, with a significance level set at p < 0.05. The results indicated that all samples endured the thermomechanical loading without complications. The highest mean bending moments were measured in angled abutments and ceramic implants, with the Ti-Zr-25 group achieving 303 ± 86 Ncm, the CI-25 group 434 ± 71 Ncm, the Ti-Zr-0 group 241 ± 45 Ncm, and the CI-0 group 326 ± 58 Ncm. Angled abutments (p = 0.001) and ceramic implants (p < 0.001) exhibited significantly greater stability compared to straight abutments and titanium implants. While titanium implants showed only plastic deformation under stress, twelve of the sixteen ceramic implants exhibited fracture. The present findings suggest that angled titanium bases and ceramic implants exhibit higher resistance to mechanical stresses under the tested parameters. This study provides valuable insights for implantology, particularly regarding the selection of abutment design and implant material. In this context, angled titanium abutments in combination with ceramic implants could be recommended as a promising alternative to the gold standard of titanium implants with straight abutments. | |||||||
Lizenz: | ![]() Dieses Werk ist lizenziert unter einer Creative Commons Namensnennung 4.0 International Lizenz | |||||||
Fachbereich / Einrichtung: | Medizinische Fakultät | |||||||
Dokument erstellt am: | 17.07.2025 | |||||||
Dateien geändert am: | 17.07.2025 | |||||||
Promotionsantrag am: | 24.02.2025 | |||||||
Datum der Promotion: | 10.07.2025 |