Method: HGFs were cultured on smooth polished (PT) and sand-blasted, acid-etched titanium (SLA) disks (Straumann). Immunocytochemistry was performed to assess localization of integrins (β1, β3, β5, α5, αvβ3, and αvβ5), vinculin, phosphorylated-cortactin, and tensin-1, after 6 and 24 h and fibronectin deposition and α-smooth muscle actin-positive stress fibers at 0.25, 1, 7 and 14 d. Periostin, versican, biglycan, and decorin were assessed using immunocytochemistry and Extracellular Matrix RT² Profiler PCR Array was performed at 1 and 7 d.
Result: Faster assembly of adhesions was seen on PT at 24 h compared to SLA with αVβ3 the predominant integrin in focal adhesions. Fibronectin deposition was lower on SLA compared to PT at 6 and 24 h, but extensive fibrillar fibronectin deposition was seen on at both PT and SLA at 1 and 2 wks. Myofibroblast differentiation was only observed on PT. Periostin secretion was lower, whereas biglycan and decorin were higher, on SLA. PCR array demonstrated that of 84 genes, increases in 15 and 16 genes on SLA at 1 and 7 d. The fibrotic mediator connective tissue growth factor was significantly reduced on SLA at 7 d (p<0.05), whereas >1000-fold increases in MMP-7, 8, and 9, PECAM-1, and TIMP3 mRNA levels on SLA were detected.
Conclusion: We conclude that rough titanium elicits decreased fibrotic and elevated tissue-remodeling responses compared to smooth titanium, and thus shows a competitive advantage for implant abutments to avoid fibrosis during healing.