title: Processing, characterization, and in vitro/in vivo evaluations of powder metallurgy processed Ti-13Nb-13Zr alloys.
abstract: This article presents details of processing, characterization and in vitro as well as in vivo evaluations of powder metallurgy processed Ti-13Nb-13Zr samples with different levels of porosity. Sintered samples were characterized for density, crystalline phases (XRD), and microstructure (SEM and EDX). Samples sintered at 1000 degrees C showed the highest porosity level ( approximately 30%), featuring open and interconnected pores ranging from 50 to 100 mum in diameter but incomplete densification. In contrast, samples sintered at 1300 and 1500 degrees C demonstrated high densification with 10% porosity level distributed in a homogeneous microstructure. The different sintering conditions used in this study demonstrated a coherent trend that is increase in temperature lead to higher sample densification, even though densification represents a drawback for bone ingrowth. Cytotoxicity tests did not reveal any toxic effects of the starting and processed materials on surviving cell percentage. After an 8-week healing period in rabbit tibias, the implants were retrieved, processed for nondecalcified histological evaluation, and then assessed by backscattered electron images (BSEI-SEM) and EDX. Bone growth into the microstructure was observed only in samples sintered at 1000 degrees C. Overall, a close relation between newly formed bone and all processed samples was observed.
authors.affiliation: Materials Science and Technology Center, Institute for Energy and Nuclear Research, São Paulo, São Paulo 05508-000, Brazil.
authors.forename: Marco C
authors.initials: MC
authors.lastname: Bottino
authors.forename: Paulo G
authors.initials: PG
authors.lastname: Coelho
authors.forename: Vinicius A R
authors.initials: VA
authors.lastname: Henriques
authors.forename: Olga Z
authors.initials: OZ
authors.lastname: Higa
authors.forename: Ana H A
authors.initials: AH
authors.lastname: Bressiani
authors.forename: José C
authors.initials: JC
authors.lastname: Bressiani
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D008855:Microscopy, Electron, Scanning; D019736:Prostheses and Implants; D011817:Rabbits; D013696:Temperature; D014025:Titanium / Q000737:chemistry* / Q000633:toxicity; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: C090153:titanium alloy (TiNb13Zr13); D014867:Water; D014025:Titanium