Hydroxyapatite coating on titanium endosseous implants for improved osseointegration: Physical and chemical considerations.

BACKGROUND

For many years, hydroxyapatite (HA) has been used as a bioactive endosseous dental implant coating to improve osseointegration. As such, the coating needs to be of high purity, adequate thickness, crystalline, and of a certain roughness in order to stimulate rapid fixation and form a strong bond between the host bone and the implant. There are a number of ways of preparing the HA coating, resulting in various coating properties. Herein, we report the preparation of the HA coating using a direct electrochemical method without the need for subsequent heat treatment.

OBJECTIVES

The aim of this study was to investigate the physicochemical properties of the HP coating, deposited on titanium implants by a modified electrochemical method.

MATERIAL AND METHODS

The coating was characterized in terms of surface chemical composition, structure, morphology, coating thickness and roughness.

RESULTS

The coating was found to be composed of homogenous HA with Ca/P and Ca/O ratios of 1.62 and 0.35, respectively. No other forms of calcium phosphate were detected. The degree of crystallinity of HA was 92.4%. The surface roughness was moderate (Sa = 1.04 μm) with the coating thickness of 2-3 μm. The scanning electron microscopy (SEM) analysis revealed a uniform, integrated layer of rod-like HA crystals with the longitudinal axes parallel to the implant surface.

CONCLUSIONS

The coating reported herein was found to have potentially favorable chemical and physical characteristics fostering osseointegration.