“The adjacent bone bears hardly any load any more, and even deteriorates in the worst case. Then the implant becomes loose and has to be replaced,” explains Dr.-Ing. Peter Quadbeck of the Fraunhofer Institute for Manufacturing and Advanced Mate- rials IFAM in Dresden. Quadbeck coordinates the “TiFoam” Project, which yielded a titanium-based substance for a new generation of implants. The foam-like structure of the substance resembles the spongiosa found inside the bone.
The titanium foam is the result of a powder metal- lurgy-based molding process that has already pro- ven its value in the industrial production of ceramic filters for aluminum casting. Open-cell polyurethane (PU) foams are saturated with a solution consisting of a binding medium and a fine titanium powder. The powder cleaves to the cellular structures of the foams. The PU and binding agents are then vapo- rized. What remains is a semblance of the foam structures, which is ultimately sintered.
“The mechanical properties of titanium foams made this way closely approach those of the human bone,” reports Quadbeck. “This applies foremost to the balance between extreme durability and minimal rigidity.” The former is an important precondition for its use on bones, which have to sustain the forces of both weight and motion. Bone-like rigidity allows for stress forces to be transmitted; with the new formati- on of bone cells, it also fosters healing of the implant. Consequently, stress can and should be applied to the implant immediately after insertion.
In the “TiFoam” project, the research partners con- centrated on demonstrating the viability of titanium foam for replacement of defective vertebral bodies.
10-09 :: September 2010
The foam is equally suitable for “repairing” other severely stressed bones. In addition to the materials scientists from the Fraunhofer institutes IFAM and IKTS – the Institute for Ceramic Technologies and Systems in Dresden – physicians from the medical center at the Technical University of Dresden and from several companies were involved in developing the titanium foam. Project partner InnoTERE already announced that it would soon develop and manufac- ture “TiFoam”-based bone implants.
Dr.-Ing. Peter Quadbeck & Cornelia Müller, Dresden Branch of the Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM):
Direct Biological Conversion of Solar Energy to Volatile Hydrocarbon Fuels by Engineered Cyanobacteria (DirectFuel)
The Albert-Ludwigs-University Freiburg participates in the new EU-funded FP7 collaborative project „Direct biological conversion of solar energy to volatile hydrocarbon fuels by engineered cyano- bacteria“ (Acronym: DirectFuel), starting OCT 1, 2010, with Prof. Wolfgang Hess, Department of Genetics, Faculty of Biology, as the principal investi- gator. The 9-partner project is coordinated from the University of Turku, Finland and is carried out over 4 years, with a total maximum project funding of EUR3,729,519.
The consortium includes partners in seven countries: Finland, Germany, UK, USA, Denmark, Italy and the Czech Republic. The DirectFuel project is combining