Hydroxyapatite coating on a titanium metal substrate by a discharging method in modified artificial body fluid

Int J Oral Maxillofac Implants. 2004 Jan-Feb;19(1):66-72.

Abstract

Purpose: The aim of this study was to evaluate the formation of a hydroxyapatite coating on titanium plate by discharging in typical and modified artificial body fluids.

Materials and methods: Japanese Industrial Standard Grade 2 titanium plates were used as specimens. Discharging was performed on the specimens in each solution, and the surface topography of each coating was observed with a scanning electron microscope. The Ca/P atomic ratio and surface characterization of each coating were evaluated by x-ray photoelectron spectroscopy, and crystal phases of each coating were analyzed by Fourier transform infrared spectroscopy and x-ray diffraction.

Results: Tricalcium phosphate formed on the titanium surface in a 1.5 Ca/P solution with high ion concentrations of calcium (2.5 mmol/L) and phosphorous (1.67 mmol/L). Crystalline HA was formed on the titanium surface in a 1.5 Ca/P solution (Hanks' balanced salt solution without organic molecules) with low ion concentrations of calcium (1.26 mmol/L) and phosphorus (0.83 mmol/L).

Discussion: A solution containing organic pH buffer was insufficient to form stable coatings on the titanium surface. Coating properties strongly depended on the Ca/P chemical ratio of the applied solution. A Ca/P ratio of 1.5 was appropriate for preparing a calcium phosphate coating on a titanium surface, whereas a Ca/P ratio of 2.5 was excessively high.

Conclusion: These findings suggest that Hanks' balanced salt solution without organic molecules is the most suitable solution for forming crystalline hydroxyapatite coatings on titanium surfaces by the discharging method.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Body Fluids / chemistry
  • Calcium Phosphates / chemistry
  • Coated Materials, Biocompatible*
  • Crystallization
  • Durapatite*
  • Electrolytes / chemistry
  • Electron Probe Microanalysis
  • Electroplating
  • Hydrogen-Ion Concentration
  • Isotonic Solutions / chemistry*
  • Microscopy, Electron, Scanning
  • Spectroscopy, Fourier Transform Infrared
  • Surface Properties
  • Titanium*

Substances

  • Calcium Phosphates
  • Coated Materials, Biocompatible
  • Electrolytes
  • Hanks Balanced Salt Solution
  • Isotonic Solutions
  • alpha-tricalcium phosphate
  • tetracalcium phosphate
  • calcium phosphate, monobasic, anhydrous
  • Durapatite
  • calcium phosphate
  • Titanium
  • calcium phosphate, dibasic, anhydrous