Adhesion of bioactive glass coating to Ti6A14V oral implant.

Bioactive glass (BAG) is a bioactive material with a high potential as implant material. Reactive plasma spraying produces an economically feasible BAG-coating for Ti6A14V oral implants. This coating is only functional if it adheres well to the metal substrate and if it is strong enough to transfer all loads. To examine these two properties an appropriate mechanical adhesion test, the moment test, is developed. This test quantifies under a realistic loading condition the corresponding functional adhesion strength to be >84 MPa in tensile. To get a qualitative insight in the BAG-coating behavior during loading the mechanical test was combined with finite element analysis, acoustic emission and microscopic analysis. These analyses showed that the coating withstands without any damage an externally generated tensile stress of 47 MPa. Not only the initial adhesion is determining for the implant quality, but more important is the coating functionality after reaction of the BAG. Adhesion testing after two months of in vitro reaction in a simulated body fluid showed that coating adhesion strength decreased with 10%, but the implant system was still adequate for load-bearing applications.

[1]  E. Rybicki,et al.  Effects of coating thickness and residual stresses on the bond strength of ASTM C633-79 thermal spray coating test specimens , 1994 .

[2]  T. Yamamuro,et al.  A new glass-ceramic for bone replacement: evaluation of its bonding to bone tissue. , 1985, Journal of biomedical materials research.

[3]  P. Tranquilli,et al.  Evaluation of different preparations of plasma-spray hydroxyapatite coating on titanium alloy and duplex stainless steel in the rabbit , 1994 .

[4]  J. Schrooten,et al.  Young's modulus of bioactive glass coated oral implants: Porosity corrected bulk modulus versus resonance frequency analysis , 1999 .

[5]  L. Hench,et al.  The bonding of Bioglass to a cobalt-chromium surgical implant alloy. , 1986, Biomaterials.

[6]  R. Pilliar,et al.  Mechanical Characterisation of Plasma-Sprayed Hydroxyapatite-Titanium Alloy Interfaces , 1991 .

[7]  M. Mazzocchi,et al.  Coating of ZrO2 supports with a biological glass , 1998, Journal of materials science. Materials in medicine.

[8]  A. G. Evans,et al.  Fracture Mechanics Determinations , 1974 .

[9]  J. Robertson,et al.  Limits to adherence of oxide scales , 1990 .

[10]  S. Giannini,et al.  Bioceramics in orthopaedic surgery: state of the art and preliminary results. , 1992, Italian journal of orthopaedics and traumatology.

[11]  P. Ducheyne,et al.  Bioactive material template for in vitro synthesis of bone. , 1995, Journal of biomedical materials research.

[12]  J. Schrooten,et al.  Glasses and bioglasses : synthesis and coatings , 1997 .

[13]  C. Berndt,et al.  Measurement of adhesion for thermally sprayed materials , 1993 .

[14]  A. Evans,et al.  Fracture Mechanics of Ceramics , 1986 .

[15]  T. Yamamuro,et al.  Bone-bonding behavior under load-bearing conditions of an alumina ceramic implant incorporating beads coated with glass-ceramic containing apatite and wollastonite. , 1995, Journal of biomedical materials research.

[16]  A. S. Tetelman,et al.  Failure Prediction in Brittle Materials Using Fracture Mechanics and Acoustic Emission , 1974 .

[17]  C. Berndt.  Tensile adhesion testing methodology for thermally sprayed coatings , 1990 .

[18]  J. Mackenzie,et al.  Bioactivity of sol–gel derived organically modified silicates: Part I: In vitro examination , 1997, Journal of materials science. Materials in medicine.

[19]  L. Hench.  Bioceramics and the origin of life. , 1989, Journal of biomedical materials research.

[20]  A. Cacchioli,et al.  Bioactive glass coating: physicochemical aspects and biological findings. , 1995, Biomaterials.

[21]  C. Berndt,et al.  Acoustic emission studies on thermal spray materials , 1998 .

[22]  Heinrich Gru¨tzner,et al.  A novel shear test for plasma-sprayed coatings , 1991 .

[23]  Origin and Detection of Microflaws in Glass , 1974 .

[24]  J. Schrooten,et al.  Adhesion of new bioactive glass coating. , 1999, Journal of biomedical materials research.

[25]  C. V. van Blitterswijk,et al.  Initial bone matrix formation at the hydroxyapatite interface in vivo. , 1995, Journal of biomedical materials research.

[26]  P. Chalker,et al.  A review of the methods for the evaluation of coating-substrate adhesion , 1991 .

[27]  H. Nishimura,et al.  Critical Stress of Microcracking in Alumina Evaluated by Acoustic Emission , 1992 .

[28]  H. Evans,et al.  Mechanical failure of thin brittle coatings , 1995 .

[29]  H. Herø,et al.  Bioactive glass ceramic on titanium substrate: the effect of molybdenum as an intermediate bond coating. , 1986, Biomaterials.

[30]  R. Happonen,et al.  Bioactive glass and glass-ceramic-coated hip endoprosthesis: experimental study in rabbit , 1995 .