Study on the enhancing micro-roughness of porous surfaced dental implant through anodization

Yoon, Tae Ho; Song, Kwang Yeob

Abstract

STATEMENT OF PROBLEM: HA has been used as a coating material on Ti implants to improve osteoconductivity. However, it is difficult to form uniform HA coatings on implants with complex surface geometries using a plasma spraying technique. PURPOSE: To determine if Ti6Al4V sintered porous-surfaced implants coated with HA solgel coated and hydrothermal treated would accelerate osseointegration.
MATERIALS AND METHODS
Porous implants which were made by electric discharge were used in this study. Implants were anodized and hydrothermal treatment or HA sol-gel coating was performed. Hydrothermal treatment was conducted by high pressure steam at 300 degrees C for 2 hours using a autoclave. To make a HA sol, triethyl phosphite and calcium nitrate were diluted and dissolved in anhydrous ethanol and mixed. Then anodized implant were spin-coated with the prepared HA sols and heat treated. Samples were soaked in the Hanks' solution with pH 7.4 at 37 degrees C for 6 weeks. The microstructure of the specimens was observed with a scanning electron microscope (SEM), and the composition of the surface layer was analyzed with an energy dispersive spectroscope (EDS).
RESULTS
The scanning electron micrographs of HA sol-gel coated and hydrothermal treated surface did not show any significant change in the size or shape of the pores. After immersion in Hanks' solution, the precipitated HA crystals covered macro- and micro-pores. The precipitated Ca and P increased in Hanks' solution that surface treatment caused increased activity.
CONCLUSION
This study shows that sol-gel coated HA and hydrothermal treatment significantly enhance the rate of HA formation due to the altered surface chemistry.