Strength of irradiated bone

A surface of the bone is a site, where the highest mechanical tensions are developed. Therefore, this place has a special importance to provide the strength. The latter depends on a bone tissue atomic/molecular structure. The present report reviews recent results demonstrating how damaged atomic/molecular bonds situated in the surface layer (interface) of the bone have an influence on its strength. The bonds were excited owing to ultraviolet radiation (UR) supplied by a Mercury tube. As the result the strength was decreased. To explore the reason of this phenomenon the atomic force microscopy operated in a tapping mode (AFM) and photoelectron (PE)/exoelectron (EE) analysis was applied. AFM demonstrated a surface topography varied from a homogenize to an island-type under UR. Such a behavior was repeated periodically in monotonically increased radiation exposure. Selective etching of the bone evidenced that reconstruction of the interface layer coupling mineral and organic phases stipulated such a synergetic. EE demonstrated a concentration of destroyed bonds also had a similar regularity depended on exposure. PE measurements discovered responsible for this centres placed at 5.35 and 5.65 eV below a vacuum level.