 Astra Tech
BioManagement Complex
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 Osseo Speed
OsseoSpeed™ is the implant with a chemically modified surface and a unique nanoscale topography. The OsseoSpeed implant has clearly improved results compared to earlier generations of implants. The following summaries of the pre-clinical and clinical scientific articles reveal the mechanisms behind the performance and clinical outcome.
 Effects of fluoride-modified titanium surfaces on osteoblast proliferation and gene expression
Purpose: Implant surface topographies which have been shown to influence the differentiation and proliferation of osteoblasts, and the upregulation of transcription factors responsible for the expression of bone matrix formation genes. The purpose of the current study was to evaluate how the application of fluoride to a well defined rough surface affects these factors.
Materials and Methods: Titanium discs were treated with either titanium grit blasting with 25 pm particles (TB, TiOblast'") or titanium grit blasting followed by treatment with dilute hydrofluoric acid (TBF, OsseoSpeed'"). An additional group of extra rough discs blasted with 125 pm particles were also prepared (ER, extra rough).
All surfaces were studied for comparative topography under scanning electron microscopy (SEM).
Discs were seeded with micromass cultures of human embryonic palatal mesenchymal cells with 50,000 cells/10 pL and left to grow for 72 hours, at which time SEM was used to study cell attachment and morphology on the TB and TBF surfaces. Tissue culture plastic (TCP) was used as a control.
Cell proliferation was evaluated at 1, 3 and 7 days, respectively.
Alkaline phosphatase (ALP) activity was analyzed using a commercial kit and a KC4 microplate data acquisition software, to measure the phosphate concentration per culture (pmol/750 pL).
In addition to this, expression of ALP, core binding-factor- 1 (Cbfal), osterix (Ox), type I collagen (Col I), bone sialoprotein (BSP II) and osteocalcin (Oc) were analyzed on cells from all rough surfaces using real time PCR strategies performed in 96-well Optical Reaction Plates in an ABI Prism 7700 Sequence Detec-tion System. Statistical analysis was performed using one-way ANOVA with Tukey'ร Multiple Comparison test.
Results: The SEM revealed all surfaces to have an isotropic topography with the TB being the smoothest and the TBF and ER having similar topographies.
At high magnification (xl0,000) the TBF demonstrated secondary nanopores.
After 72 hours there was evidence of cell spreading with flattened cells on all surfaces.
ALP activity was significantly lower for TCP compared to all titanium discs, but more so compared to TBF and ER, at days 3 and 7 (p < 0.001). However, there was no significant difference between the different titanium groups (at 3 and 7 days).
With respect to cell proliferation, all discs demonstrated a progressive increase in cell numbers, but by day 3 TCP the smooth control surface demonstrated a significantly higher number of cells when compared to all 3 rough surfaces, (p < 0.001). There were no significant differences between the TBF and ER surface. By the end of the week TB and TCP were comparable but TBF and ER demonstrated a net reduction in cell numbers by 20%, (p < 0.001) compared to TB and TCP.
With respect to gene expression TBF demonstrated a significant increase in Cfbal compared to the other titanium surfaces at 7 days, (p < 0.01), doubling between days 3 and 7. Osteocalcin also increased from day 3 to 7 for all surfaces, while the levels for the other gene expression markers were the same for all surfaces at all time points.
Discussion and Conclusions: In the current study smoother surfaces were shown to optimize cell proliferation, however the application of fluoride ions appeared to optimize the upregulation of Cfbal, a transcription factor that is essential for the maturation and differentiation of mesenchymal stem cells into osteoblasts. Other factors such as cell spreading and ALP activity were comparable between titanium surfaces. This suggests the OsseoSpeed surface may be better disposed to support and promote cellular differentiation and potential to enhance osteogenesis. |
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