HA/DLC COMPOSITE COATINGS FOR IMPROVED BIOACTIVITY AND BIOCOMPATIBILITY OF ORTHOPAEDIC PROSTHESES

摘要

Bioactive coatings made of hydroxyapatite (HA) mimic the mineral composition of natural bone. Unfortunately, problems with adhesion, poor chemical and mechanical integrity, and incomplete bone ingrowth limit the use of current hydroxyapatite surfaces. We have developed a novel technique using pulsed laser deposition to produce bioactive hydroxyapatite surfaces on a diamondlike carbon (DLC) interlayer. DLC is an amorphous, hydrogen-free, and primarily sp~3-bonded form of carbon that exhibits exceptional biocompatibility, wear and corrosion resistance, and mechanical properties. The underlying titanium substrate is first coated with DLC using pulsed laser deposition (PLD). The DLC surface is then coated with HA to form the final bilayer material. The films were characterized using SEM, TEM, XRD, Raman spectroscopy, and mechanical testing. HA/DLC bilayers are promising for use in several different orthopaedic implant designs.