title: Mechanical property assessment of bone healing around a titanium-zirconium alloy dental implant.
abstract: BACKGROUND
  It has been reported that titanium-zirconium alloy with 13-17% zirconium (TiZr1317) implants show higher biomechanical stability and bone area percentage relative to commercially pure titanium (cpTi) grade 4 fixtures.
  
  
  OBJECTIVE
  This study aimed to determine whether the higher stability for TiZr1317 implants is associated with higher mechanical properties of remodeling bone in the areas around the implants.
  
  
  METHODS
  This study utilized 36 implants (n = 18: TiZr1317, n = 18: cpTi), which were placed in the healed ridges of the mandibular premolar and first molar of 12 mini pigs (n = 3 implants/animal). After 4 weeks in vivo, the samples were retrieved, and resin-embedded histologic sections of approximately 100 μm in thickness were prepared. In order to determine the nanomechanical properties, nanoindentation (n = 30 tests/specimen) was performed on the bone tissue of the sections under wet conditions with maximum load of 300 μN (loading rate: 60 μN/s).
  
  
  RESULTS
  The mean (± standard deviation) elastic modulus (E) and hardness (H) for the TiZr1317 group were 2.73 ± 0.50 GPa and 0.116 ± 0.017 GPa, respectively. For the cpTi group, values were 2.68 ± 0.51 GPa and 0.110 ± 0.017 GPa for E and H, respectively. Although slightly higher mechanical properties values were observed for the TiZr1317 implants relative to the cpTi for both elastic modulus and hardness, these differences were not significant (E = p > 0.75; H = p > 0.59).
  
  
  CONCLUSIONS
  The titanium-zirconium alloy used in this study presented similar degrees of nanomechanical properties to that of the cpTi implants.
authors.affiliation: Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY, USA; Sao Paulo State University, Araçatuba Dental School-UNESP, Araçatuba, SP, Brazil.
authors.forename: Rodolfo B
authors.initials: RB
authors.lastname: Anchieta
authors.forename: Marta
authors.initials: M
authors.lastname: Baldassarri
authors.forename: Fernando
authors.initials: F
authors.lastname: Guastaldi
authors.forename: Nick
authors.initials: N
authors.lastname: Tovar
authors.forename: Malvin N
authors.initials: MN
authors.lastname: Janal
authors.forename: Jan
authors.initials: J
authors.lastname: Gottlow
authors.forename: Michel
authors.initials: M
authors.lastname: Dard
authors.forename: Ryo
authors.initials: R
authors.lastname: Jimbo
authors.forename: Paulo G
authors.initials: PG
authors.lastname: Coelho
mesh_terms: D000497:Alloys / Q000737:chemistry*; D000818:Animals; D001696:Biomechanical Phenomena; D016723:Bone Remodeling / Q000502:physiology*; D000069343:Bone-Implant Interface / Q000033:anatomy & histology / Q000502:physiology; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry*; D055119:Elastic Modulus; D005260:Female; D006244:Hardness; D008334:Mandible / Q000033:anatomy & histology / Q000502:physiology*; D008422:Materials Testing; D036103:Nanotechnology; D016348:Osseointegration / Q000502:physiology; D013314:Stress, Mechanical; D013552:Swine; D013556:Swine, Miniature; D014025:Titanium / Q000737:chemistry*; D014945:Wound Healing / Q000502:physiology
chemical_list: D000497:Alloys; D015921:Dental Implants; D003764:Dental Materials; C000599177:Ti-Zr alloy; D014025:Titanium
keywords: animal model; biomechanics; bone; dental/endosteal implants; nanoindentation