Osteoblastic and cytokine gene expression of implant-adherent cells in humans.
OBJECTIVE
Implant surface topography is a key determinant affecting osteoblastic differentiation and cell-cell signaling of implant-adherent cells.


METHODS
To assess the early osteoinductive and cell-cell signaling events in adherent cells, commercially pure titanium implants (2.2 × 5 mm) with nanotopography (HF-treated TiO2 grit-blasted) were compared with micron-scale topography TiO2 grit-blasted (micron-scale, control) implants in vivo. Six implants (n = 3/surface) were placed in 10 systemically healthy subjects and removed by reverse threading at 1, 3, and 7 days. Gene expression profiles of adherent cells were interrogated using low-density RT-PCR arrays.


RESULTS
Osteoinduction was not observed at day 1 on either surface. At 3 days, elevated levels of BMP6, osteopontin, and osterix (OSX) were observed in RNA of cells adherent to both micron-scale and nanotopography surfaces. Both surfaces supported osteoinductive gene expression at 7 days; however, modest elevations of most mRNAs and significantly higher OSX mRNA levels were measured for cells adhered to nanotopography implants. Further, chemokine and cytokine profiles including CXCL10, CXCL14, IL-9, IL-22, and TOLLIP were upregulated on nanotopographic surfaces as compared with microtopographic surfaces.


CONCLUSIONS
Implants with superimposed nanoscale topography generate a greater induction of genes linked to osteogenesis and cell-cell signaling during the early phases of osseointegration.
Department of Prosthodontics, University of North Carolina, Chapel Hill, NC, USA; Department of Prosthodontics, Ohio State University, Columbus, OH, USA.
Matthew
M
Bryington
Gustavo
G
Mendonça
Salvador
S
Nares
Lyndon F
LF
Cooper
D000293:Adolescent; D000328:Adult; D000368:Aged; D002454:Cell Differentiation; D016207:Cytokines / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D010006:Osteoblasts / Q000378:metabolism*; D010012:Osteogenesis / Q000235:genetics*; D053495:Osteopontin / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013499:Surface Properties; D014025:Titanium
D016207:Cytokines; D012333:RNA, Messenger; D053495:Osteopontin; D014025:Titanium