Effects of artificial aging conditions on yttria-stabilized zirconia implant abutments

Autor: João Neudenir Arioli Filho, Gildo Coelho Santos Junior, Amin S. Rizkalla, Mariana de Almeida Basílio, Selma Gutierrez Antonio, Kátia Vieira Cardoso
Přispěvatelé: School of Dentistry, Universidade Estadual Paulista (Unesp), Schulich School of Medicine & Dentistry, Metropolitan Union Educ & Culture, Western Univ
Rok vydání: 2016
Předmět:
Zdroj: Bone and Joint Institute
ResearcherID
Scopus
Repositório Institucional da UNESP
Universidade Estadual Paulista (UNESP)
instacron:UNESP
Web of Science
ISSN: 0022-3913
DOI: 10.1016/j.prosdent.2016.01.011
Popis: Made available in DSpace on 2018-12-11T17:01:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-08-01 Statement of problem Most ceramic abutments are fabricated from yttria-stabilized tetragonal zirconia (Y-TZP). However, Y-TZP undergoes hydrothermal degradation, a process that is not well understood. Purpose The purpose of this in vitro study was to assess the effects of artificial aging conditions on the fracture load, phase stability, and surface microstructure of a Y-TZP abutment. Material and methods Thirty-two prefabricated Y-TZP abutments were screwed and tightened down to external hexagon implants and divided into 4 groups (n = 8): C, control; MC, mechanical cycling (1×106 cycles; 10 Hz); AUT, autoclaving (134°C; 5 hours; 0.2 MPa); and TC, thermal cycling (104 cycles; 5°/55°C). A single-load-to-fracture test was performed at a crosshead speed of 0.5 mm/min to assess the assembly's resistance to fracture (ISO Norm 14801). X-ray diffraction (XRD) analysis was applied to observe and quantify the tetragonal-monoclinic (t-m) phase transformation. Representative abutments were examined with high-resolution scanning electron microscopy (SEM) to observe the surface characteristics of the abutments. Load-to-fracture test results (N) were compared by ANOVA and Tukey test (α=.05). Results XRD measurements revealed the monoclinic phase in some abutments after each aging condition. All the aging conditions reduced the fracture load significantly (P
Databáze: OpenAIRE