실패한 임플란트 고정체의 표면분석과 특성

Abstract

It has been hypothesized that surface contaminants may be released from contaminated implant surface, enhancing and perpetuating the inflammatory response, thus altering the healing process and possibly provoking the dissolution of titanium. In addition, the alterations of this oxide layer surface may difficult the re-osseointegration. Several longitudinal studies have reported high survival and success rates for dental implants. Nevertheless, dental implant failures due to peri-implant infection have also been reported. The aim of this investigation was to analyze surface characteristics of clinically failed implant fixture in order to determine possible causes of failure. The failed implants were classified into three groups; 3 and 5 month used implant, 19 and 60 month used implant, and fractured implant, after implantation for 33 month and 120 month in patient jaws. The topography and surface chemical composition were studied with energy dispersive x-ray spectroscopy(EDS) and field emission scanning electron microscope(FE-SEM) to analyze element on the surface of flank and bottom of thread. Evaluations were performed at the upper, middle and lower implant fixture. The results were as follows: 1. From surface observation of 3 and 5 month used implant, contaminants were detected in the middle and lower part of implants. Overall, foreign elements such as silicon, carbon, oxygen, zinc, sulfur, zirconium, and chloride were detected in failed implants. These elements showed predominantly at bottom of thread. And corrosion phenomena appeared in the bottom of thread that was accumulated chloride. 2. From surface observation of 19 and 60 month used implant, the corrosion was accelerated at the bottom of thread that was accumulated chloride. Corrosion products showed in the bottom of thread including dissoluted elements, such as Au, Cu, Ag, from suprastructure of dental implant system. 3. From surface observation of fatigue fractured implants, The crack were nucleated in the bottom of thread and the crack of corrosion fatigue was predominantly propagated. The corrosion products including chloride were found opposite side of starting point of corrosion fatigue crack. we could find the fatigue striation and estimate the dimple fracture of implants. These results suggest that chloride, and corrosion products-related cause for dental implant failures. In order to protect the corrosion fatigue and contamination, we must consider the implant manufacturing and surface modification of implant materials.