title: Mechanical behavior of zirconia and titanium abutments before and after cyclic load application.
abstract: BACKGROUND
  Esthetic factors influence the decision to use titanium or zirconia abutments in anterior regions. Clinicians may have concerns about the durability and behavior of these zirconia abutments.
  
  
  OBJECTIVE
  The purpose of this in vitro study was to evaluate the longitudinal and transverse long axes of the implant-abutment interface before and after the cyclic loading of titanium and zirconia abutments with an external hexagon.
  
  
  METHODS
  Forty dental implants with an external hexagon and 40 corresponding abutments made of titanium (Ti) and zirconia (Zr) were subjected to cyclic load (c1) versus no load (c2). The longitudinal and transverse axes of 4 experimental groups (Tic1, Tic2, Zrc1, and Zrc2) were analyzed (vertical/horizontal adjustment) using a scanning electron microscope at ×1000 magnification. The differences among the groups were determined by 1-way analysis of variance (ANOVA) and post hoc Tukey tests (α=.05). T tests were used to identify the statistically significant differences between each group and each condition (α=.05).
  
  
  RESULTS
  Significant differences were found among the groups with respect to the misfits analyzed in the 2 sections (longitudinal and transverse) before and after load application (P<.05). The behaviors of the groups differed particularly with regard to the accommodation of sets (abutment/implant) after the application of cyclic loads (P<.05).
  
  
  CONCLUSIONS
  The use of zirconia abutments in titanium implants can cause changes to and/or permanent deformation of the implant hexagon.
authors.affiliation: Researcher, Department of Research, Biotecnos Research Center, Santa Maria, Brazil. Electronic address: sergio.gehrke@hotmail.com.
authors.forename: Sergio Alexandre
authors.initials: SA
authors.lastname: Gehrke
authors.affiliation: Graduate student, Department of Engineering, Industrial Technique College of the Federal University of Santa Maria, Santa Maria, Brazil.
authors.forename: Pablo Mateus
authors.initials: PM
authors.lastname: Poncio da Silva
authors.affiliation: Full Professor, Department of Research, Faculty of Medicine and Dentistry San Antonio Catholic University of Murcia, Murcia, Spain.
authors.forename: José Luiz
authors.initials: JL
authors.lastname: Calvo Guirado
authors.affiliation: Associate Professor, Department of Prosthodontics and Digital Technology, Stony Brook University School of Dental Medicine, Stony Brook, New York.
authors.forename: Rafael Arcesio
authors.initials: RA
authors.lastname: Delgado-Ruiz
authors.affiliation: Full Professor, Department of Materials Engineering, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Berenice Anina
authors.initials: BA
authors.lastname: Dedavid
authors.affiliation: Graduate student, Department of Periodontology and Oral Implantology, Dental Research Division, University of Guarulhos, Guarulhos, Brazil.
authors.forename: Magda
authors.initials: M
authors.lastname: Aline Nagasawa
authors.affiliation: Titular Professor, Department of Periodontology and Oral Implantology, Dental Research Division, University of Guarulhos, Guarulhos, Brazil.
authors.forename: Jamil Awad
authors.initials: JA
authors.lastname: Shibli
mesh_terms: D000044:Dental Abutments; D059605:Dental Implant-Abutment Design; D003799:Dental Stress Analysis; D006244:Hardness; D006801:Humans; D066298:In Vitro Techniques; D008855:Microscopy, Electron, Scanning; D014025:Titanium; D015040:Zirconium
chemical_list: D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide