In-vitro performance and fracture strength of thin monolithic zirconia crowns
| Autor: | Hans-Christoph Lauer, Anna Lena Sander, Roland Felber, Paul Weigl, Yanyun Wu, Martin Rosentritt |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
Materials science
medicine.medical_treatment 02 engineering and technology Crown (dentistry) 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Flexural strength stomatognathic system medicine Minimal invasive Dentistry (miscellaneous) Cubic zirconia Ceramic ddc:610 Composite material Cementation Monolithic crown Zinc phosphate 030206 dentistry 021001 nanoscience & nanotechnology Cementation (geology) stomatognathic diseases chemistry visual_art Fracture (geology) visual_art.visual_art_medium Zirconia Original Article Adhesive Oral Surgery 0210 nano-technology |
| Zdroj: | The Journal of Advanced Prosthodontics |
| Popis: | PURPOSE. All-ceramic restorations required extensive tooth preparation. The purpose of this in vitro study was to investigate a minimally invasive preparation and thickness of monolithic zirconia crowns, which would provide sufficient mechanical endurance and strength. MATERIALS AND METHODS. Crowns with thickness of 0.2 mm (group 0.2, n=32) or of 0.5 mm (group 0.5, n=32) were milled from zirconia and fixed with resin-based adhesives (groups 0.2A, 0.5A) or zinc phosphate cements (groups 0.2C, 0.5C). Half of the samples in each subgroup (n=8) underwent thermal cycling and mechanical loading (TCML)(TC: 5 degrees C and 55 degrees C, 2x3,000 cycles, 2 min/cycle; ML: 50 N, 1.2x10(6) cycles), while the other samples were stored in water (37 degrees C/24 h). Survival rates were compared (Kaplan-Maier). The specimens surviving TCML were loaded to fracture and the maximal fracture force was determined (ANOVA; Bonferroni; alpha=.05). The fracture mode was analyzed. RESULTS. In both 0.5 groups, all crowns survived TCML, and the comparison of fracture strength among crowns with and without TCML showed no significant difference (P=.628). Four crowns in group 0.2A and all of the crowns in group 0.2C failed during TCML. The fracture strength after 24 hours of the cemented 0.2 mm-thick crowns was significantly lower than that of adhesive bonded crowns. All cemented crowns provided fracture in the crown, while about 80% of the adhesively bonded crowns fractured through crown and die. CONCLUSION. 0.5 mm thick monolithic crowns possessed sufficient strength to endure physiologic performance, regardless of the type of cementation. Fracture strength of the 0.2 mm cemented crowns was too low for clinical application. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|