title: Osteoinduction on acid and heat treated porous Ti metal samples in canine muscle.
abstract: Samples of porous Ti metal were subjected to different acid and heat treatments. Ectopic bone formation on specimens embedded in dog muscle was compared with the surface characteristics of the specimen. Treatment of the specimens by H2SO4/HCl and heating at 600 °C produced micrometer-scale roughness with surface layers composed of rutile phase of titanium dioxide. The acid- and heat-treated specimens induced ectopic bone formation within 6 months of implantation. A specimen treated using NaOH followed by HCl acid and then heat treatment produced nanometer-scale surface roughness with a surface layer composed of both rutile and anatase phases of titanium dioxide. These specimens also induced bone formation after 6 months of implantation. Both these specimens featured positive surface charge and good apatite-forming abilities in a simulated body fluid. The amount of the bone induced in the porous structure increased with apatite-forming ability and higher positive surface charge. Untreated porous Ti metal samples showed no bone formation even after 12 months. Specimens that were only heat treated featured a smooth surface composed of rutile. A mixed acid treatment produced specimens with micrometer-scale rough surfaces composed of titanium hydride. Both of them also showed no bone formation after 12 months. The specimens that showed no bone formation also featured almost zero surface charge and no apatite-forming ability. These results indicate that osteoinduction of these porous Ti metal samples is directly related to positive surface charge that facilitates formation of apatite on the metal surfaces in vitro.
authors: Department of Orthopedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Toshiyuki
authors: T
authors: Kawai
authors: Department of Orthopedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Mitsuru
authors: M
authors: Takemoto
authors: Department of Orthopedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Shunsuke
authors: S
authors: Fujibayashi
authors: Department of Orthopedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Haruhiko
authors: H
authors: Akiyama
authors: Department of Orthopedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Masashi
authors: M
authors: Tanaka
authors: Department of Biomedical Sciences, College of Life and Health Sciences, Chubu University, Kasugai, Aichi, Japan.
authors: Seiji
authors: S
authors: Yamaguchi
authors: Department of Biomedical Sciences, College of Life and Health Sciences, Chubu University, Kasugai, Aichi, Japan.
authors: Deepak K
authors: DK
authors: Pattanayak
authors: Osaka Yakin Kogyo Co., ltd., Osaka, Japan.
authors: Kenji
authors: K
authors: Doi
authors: Department of Biomedical Sciences, College of Life and Health Sciences, Chubu University, Kasugai, Aichi, Japan.
authors: Tomiharu
authors: T
authors: Matsushita
authors: National Hospital Organization Kyoto Medical Center, Kyoto, Japan.
authors: Takashi
authors: T
authors: Nakamura
authors: Department of Biomedical Sciences, College of Life and Health Sciences, Chubu University, Kasugai, Aichi, Japan.
authors: Tadashi
authors: T
authors: Kokubo
authors: Department of Orthopedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Shuichi
authors: S
authors: Matsuda
mesh_terms: D000818:Animals; D001031:Apatites / Q000737:chemistry; D002113:Calcification, Physiologic / Q000187:drug effects; D004285:Dogs; D006358:Hot Temperature; D008855:Microscopy, Electron, Scanning; D009132:Muscles / Q000187:drug effects* / Q000473:pathology; D016348:Osseointegration / Q000187:drug effects*; D010012:Osteogenesis / Q000187:drug effects; D016062:Porosity; D055672:Static Electricity; D013464:Sulfuric Acids / Q000494:pharmacology*; D014025:Titanium / Q000494:pharmacology*; D014961:X-Ray Diffraction
chemical_list: D001031:Apatites; D013464:Sulfuric Acids; D014025:Titanium; C033158:sulfuric acid