Bioactivity of sol-gel-derived TiO2 coating on polyetheretherketone: In vitro and in vivo studies.

Unlabelled: A polyetheretherketone (PEEK) surface was modified using a sol-gel-derived TiO2 coating in order to confer bone-bonding ability. To enhance the bonding strength of the coating layer, pretreatment with either O2 plasma or sandblasting was performed prior to sol-gel coating. Additionally, post-treatment with acid was carried out to confer apatite (calcium phosphate)-forming ability to the surface.

Apatite-forming PEEK with TiO2 surface layer coating.

Polyetheretherketone (PEEK) is widely used in orthopedic implants, such as spinal fusion devices, because of its moderate elastic modulus, as well as relatively high mechanical strength. However, it does not bond to living bone, and hence it needs autograft to be fixed to the bone. In this study, we attempted to add bone-bonding properties to PEEK by coating with TiO2 synthesized by the sol-gel process.

Antibacterial and bioactive calcium titanate layers formed on Ti metal and its alloys.

An antibacterial and bioactive titanium (Ti)-based material was developed for use as a bone substitute under load-bearing conditions. As previously reported, Ti metal was successively subjected to NaOH, CaCl2, heat, and water treatments to form a calcium-deficient calcium titanate layer on its surface. When placed in a simulated body fluid (SBF), this bioactive Ti formed an apatite layer on its surface and tightly bonded to bones in the body.

Bone bonding ability of a chemically and thermally treated low elastic modulus Ti alloy: gum metal.

The gum metal with composition Ti-36Nb-2Ta-3Zr-0.3O, is free from cytotoxic elements and exhibits a low elastic modulus as well as high mechanical strength. We have previously demonstrated that this gum metal, once subjected to a series of surface treatments--immersion in 1 M NaOH (alkali treatment) and then 100 mM CaCl2, before heating at 700 °C (sample: ACaH-GM), with an optional final hot water immersion (sample: ACaHW-GM)--has apatite-forming ability in simulated body fluid.

Effect of Ca contamination on apatite formation in a Ti metal subjected to NaOH and heat treatments.

It has long been known that titanium (Ti) metal bonds to living bone through an apatite layer formed on its surface in the living body after it had previously been subjected to NaOH and heat treatments and as a result had formed sodium titanate on its surface. These treatments were applied to a porous Ti metal layer on a total hip joint and the resultant joint has been in clinical use since 2007. It has been also demonstrated that the apatite formation on the treated Ti metal in the living body also occurred in an acelullar simulated body fluid (SBF) with ion concentrations nearly equal to those of the human blood plasma, and hence bone-bonding ability of the treated Ti metal can be evaluated using SBF in vitro.

Formation of a bioactive calcium titanate layer on gum metal by chemical treatment.

The so-called gum metal with the composition Ti-36Nb-2Ta-3Zr-0.3O is free from cytotoxic elements and exhibits a low elastic modulus as well as high mechanical strength. In the present study, it was shown that this alloy exhibited a high capacity for apatite formation in a simulated body fluid when subjected to 1 M NaOH treatment, 100 mM CaCl(2) treatment, heat treatment at 700°C, and then hot water treatment.

Effect of titania-based surface modification of polyethylene terephthalate on bone-implant bonding and peri-implant tissue reaction.

Organic polymers can be uniformly surface-modified with bioactive TiO(2) by using a sol-gel method. Titania-based surface-modified polyethylene terephthalate (TiPET) plates and fabric have shown apatite-forming ability in simulated body fluid. Here, we first investigated the bone-bonding ability and mechanical bonding strength between the surface-modified layer and the base material (PET) of TiPET plates in vivo.

Preparation of bioactive Ti metal surface enriched with calcium ions by chemical treatment.

A calcium solution treatment was applied to a NaOH-treated titanium metal to give it bioactivity, scratch resistance and moisture resistance. The titanium metal was soaked in a 5 M NaOH solution and then a 100 mM CaCl(2) solution to incorporate Ca(2+) ions into the titanium metal surface by ion exchange. This treated titanium metal was subsequently heated at 600 degrees C and soaked in hot water at 80 degrees C.

Specific response of osteoblast-like cells on hydroxyapatite layer containing serum protein.

Accelerations of bone-like apatite deposition and cell growth on an electrically polarized ceramic hydroxyapatite have been reported. A relationship between these phenomena was investigated in a previous report, and then it was suggested that osteoblast-like cell's (MC3T3-E1) growth had relevance to the mineral growth. The effect of the formed apatite layer especially appeared to be on the cell adhesion.

Effect of bone-like layer growth from culture medium on adherence of osteoblast-like cells.

The electrical polarization of ceramic HAp had an effect on the acceleration of bone restoration. Cell behavior in the bone-like growth layer was investigated. The deposits on the ceramic HAp was grown and formed layers by soaking in alpha-minimum essential medium supplemented with 10% fetal bovine serum (alpha-MEM supplemented with 10% FBS).