title: Therapeutic doses of radiation alter proliferation and attachment of osteoblasts to implant surfaces.
abstract: Osseointegration of implants in irradiated bone is inadequate. The effect of radiation on cell-implant material interaction has not been adequately studied. The goal of this study was to investigate the effects of ionizing radiationon the proliferation, differentiation, and attachment of osteoblasts to commercially pure titanium (cpTi). Human fetal osteoblasts (hFOB) were irradiated either before or after plating in tissue culture (TC) dishes with or without cpTi disks. Radiation was single dose of 10 cGy, 25 cGy, 50 cGy, 1 Gy, 2 Gy, 4 Gy or 8 Gy. Cell proliferation was determined by counting trypsinized cells on 7 days after irradiation. Attachment of irradiated hFOB was measured indirectly by counting cells 2 and 6 h after plating. Differentiation was evaluated by alkaline phosphatase activity. Compared with nonirradiated sham controls, higher doses of radiation significantly reduced cell attachment and proliferation. Both proliferation and attachment were significantly lower on cpTi compared with TC. Attachment decreased based on the length of postirradiation period. Although differentiation was significantly enhanced by a dose of 8 Gy, proliferation was lowest. These initial studies show that effects of therapeutic doses of radiation on osteoblasts varied depending on the surface, time-elapsed, and amount of radiation.
authors: Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN, USA. ahmad005@umn.edu
authors: Mansur
authors: M
authors: Ahmad
authors: Christopher
authors: C
authors: Sampair
authors: Abu N M
authors: AN
authors: Nazmul-Hossain
authors: Neerja
authors: N
authors: Khurana
authors: Andrew
authors: A
authors: Nerness
authors: Patcharaporn
authors: P
authors: Wutticharoenmongkol
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D002448:Cell Adhesion / Q000528:radiation effects; D002460:Cell Line; D049109:Cell Proliferation / Q000528:radiation effects; D005720:Gamma Rays; D006801:Humans; D020007:Implants, Experimental; D008855:Microscopy, Electron, Scanning; D010006:Osteoblasts / Q000166:cytology* / Q000201:enzymology / Q000528:radiation effects*; D013499:Surface Properties / Q000528:radiation effects; D014025:Titanium / Q000378:metabolism
chemical_list: D014025:Titanium; D000469:Alkaline Phosphatase