The effect of grain size on the biocompatibility, cell-materials interface, and mechanical properties of microwave-sintered bioceramics.
The effect of decreasing the grain size on the biocompatibility, cell-material interface, and mechanical properties of microwave-sintered monophase hydroxyapatite bioceramics was investigated in this study. A nanosized stoichiometric hydroxyapatite powder was isostatically pressed at high pressure and sintered in a microwave furnace in order to obtain fine grained dense bioceramics. The samples sintered at 1200°C, with a density near the theoretical one, were composed of micron-sized grains, while the grain size decreased to 130 nm on decreasing the sintering temperature to 900°C. This decrease in the grain size certainly led to increases in the fracture toughness by much as 54%. An in vitro investigation of biocompatibility with L929 and human MRC-5 fibroblast cells showed noncytotoxic effects for both types of bioceramics, while the relative cell proliferation rate, cell attachment and metabolic activity of the fibroblasts were improved with decreasing of grain size. An initial in vivo investigation of biocompatibility by the primary cutaneous irritation test showed that both materials exhibited no irritation properties.
Faculty of Technology and Metallurgy, University of Belgrade, Belgrade 11120, Serbia. djveljovic@tmf.bg.ac.rs
Djordje
D
Veljović
Miodrag
M
Colić
Vesna
V
Kojić
Gordana
G
Bogdanović
Zvezdana
Z
Kojić
Andrijana
A
Banjac
Eriks
E
Palcevskis
Rada
R
Petrović
Djordje
D
Janaćković
D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry* / Q000378:metabolism; D002460:Cell Line; D049109:Cell Proliferation; D002516:Ceramics / Q000737:chemistry* / Q000378:metabolism; D017886:Durapatite / Q000737:chemistry* / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D008297:Male; D008422:Materials Testing; D051379:Mice; D008872:Microwaves; D010316:Particle Size; D011817:Rabbits; D023422:Skin Irritancy Tests; D013314:Stress, Mechanical; D013499:Surface Properties
D001672:Biocompatible Materials; D017886:Durapatite