Method: Gingival fibroblasts (HGF) from human biopsies were plated on Co-Cr alloy
discs with four different topographies: smooth (4000 grit), sandblasted (60psi, 50micron AlO3), acid etched, (nitro-hydrochloric acid), and unidirectional striations (320 grit). A total of 48 discs were used in the study, four discs in each of the topography groups were treated with platelet-derived growth factor (PDGF-BB), or left untreated. After 48 hours of incubation, HGF viability was measured using MTT assay. Cellular morphology was viewed under a scanning electron microscope (SEM). The discs were treated with MTT reagent and detergent, and absorbance was read at 570nm. The cells were processed for scanning electron microscopy with after fixation in glutaraldehyde, sodium cacodylate, ethanol, and Hexamethyldisilazane (HMDS).
Result: A significantly higher number of viable cells were seen on treated surfaces
than untreated surfaces (p=0.7). The average number of HGF on PDGF-BB treated surfaces (617,000 cells) was higher than the untreated surfaces (570,000 cells). No significant difference in cell number was seen between different surface topographies within each treatment group. SEM analysis showed that fibroblasts on smooth, sandblasted, and acid etched surfaces had rounded morphology with many pseudopodia extending in all directions. Cells on these surfaces disregarded topography and spread in all areas of the disc. HGF on the unidirectional striated surface aligned within the striation with elongated morphology and few pseudopodia.
Conclusion: Growth factors promote HGF growth on metal surfaces and surface topography affects their spacial colonization and attachment.
Keywords: Fibroblasts, Implants, Metals, Surfaces and Wound healing
See more of: Implantology Research