In vivo expression of osteogenic markers and bone mineral density at the surface of fluoride-modifie
July 3rd, 2008 | by admin |In vivo expression of osteogenic markers and bone mineral density at the surface of fluoride-modified titanium implants.
The aim of the present study was to investigate the biological mechanisms of the functional attachment of fluoride-modified titanium implants to cortical bone by studying the association of the pull-out test results with gene expression of osteoblast (runx2, osteocalcin, collagen-I and IGF-I), osteoclast (TRAP, H(+)-ATPase and calcitonin receptor) and inflammation (TNF-alpha, IL-6 and IL-10) markers from peri-implant bone tissue using real-time RT-PCR, following a 4- and 8-week healing period. After implant detachment, wound fluid from the implant site was collected for LDH and ALP activity analysis. A new method to study volumetric bone mineral density (vBMD) of sub-implant cortical bone was developed using micro-computed tomography. Our results show lower LDH activity and TRAP mRNA levels in fluoride implants after 4weeks of healing, yet no differences were found either on the pull-out force or expression of bone formation marker genes. After 8weeks of healing, both pull-out, vBMD and osteocalcin, runx2 and collage type I gene expression were higher in fluoride implants. In conclusion, fluoride-modified implants seem to modulate both inflammation and bone resorption/formation events at the bone-implant interface, suggesting that these biological effects are an intrinsic part of the clinical performance of this surface.
Monjo M, Lamolle SF, Lyngstadaas SP, Rønold HJ, Ellingsen JE.
Department of Biomaterials, Institute for Clinical Dentistry, University of Oslo, P.O. Box 1109 Blindern, NO-0317 Oslo, Norway.