Research Support
SPIRITS

Development of Bioactive Novel Titanium Alloy Implant

Project Gist

Novel bioactive implants with high bone bonding ability, high mechanical properties, and high corrosion resistance.

Keywords

Implants, Titanium alloys, Apatite Nuclei, Bioactivity, Bone bonding ability

Background, Purpose, and Project Achievements

Today, we have reached the super-aged society. In order to accurately treat the bone defects caused by bone disease and improve the quality of life (QOL) of patients, demand of artificial bone has been growing more and more.

Generally, most of artificial materials are encapsulated with fibrous tissue and isolated from surrounding tissue in living body. This reaction is a normal protective reaction of living body against foreign substances. Some kinds of ceramics forms hydroxyapatite layer on their surface and bond to living bone through this layer in living body. Researcher calls these ceramics as “bioactive ceramics”. However, ceramics has low mechanical strength because of their brittleness. Implant materials with high mechanical strength as well as high bioactivity is required in the medical field.

Titanium alloys are widely used in artificial hip joint and artificial tooth because of their high mechanical strength and high corrosion resistance. Recently, we invented novel calcium phosphate fine particles, named “Apatite Nuclei”. We found that “Apatite Nuclei” can actively induce formation of hydroxyapatite, which is main inorganic component of our bone. In this study, we formed micropores on the surfaces of titanium alloys and precipitated “Apatite Nuclei” in the pores. By this treatment, we provided high bioactivity to titanium alloys and developed novel implant materials.

Future Prospects

In this program, we have conducted animal test of the bioactive titanium alloys. After the program, we will succeed to conduct experiments for further improvements in implant manufacturing conditions such as micropores formation process and “Apatite Nuclei” precipitation process, and try to invent novel implant materials with high bone formation ability, high corrosion resistance, and high mechanical strength. We aims to practical use of this implant in the world via clinical trials in the future.

Figures

Picture of untreated titanium alloy implants (left side) and bioactive titanium alloy implants (right side). The shape of bioactive implants were almost same compared with those of untreated ones.
Schematic illustration of adhesion mechanism between living bone and bioactive titanium alloy implants. In living body, hydroxyapatite, a main inorganic component of our bone, was formed in a short time and living bone directly bonds to living bone through this layer.
Picture of evaluation of bone formation on the implants conducted in London.

Principal Investigator

YABUTSUKA Takeshi

・YABUTSUKA Takeshi
・Graduate School of Energy Science
・On September 2009, the author got Ph.D. from Kyoto University. Since November 2009, the author is working on the research and the education as Asssitant Professor in Graduate School of Energy Science, Kyoto University. Focusing on a biomimetic method, ceramics synthesis process learned from a biomineralization, our research group trys to invent various kinds of multifunctional biomaterials based on an apatite which is a main inorganic component of our bone.
http://fssc.energy.kyoto-u.ac.jp/