Osteoblast Interactions with Different Microstructured Dental Implant Surfaces: Comparative Study of Cell Attachment, Migration, Proliferation, and Differentiation

Osteoblast Interactions with Different Microstructured Dental Implant Surfaces: Comparative Study of Cell Attachment, Migration, Proliferation, and Differentiation
R. SAMMONS1, N. LUMBIKANONDA1, and P. CANTZLER2, 1 University of Birmingham School of Dentistry, United Kingdom, 2 Friadent GmbH, Mannheim, Germany
2003
IADR
Objective: To compare cellular interactions with a new experimental surface and 6 different commercially-available microstructured implant surfaces.
Methods: Implant surfaces tested: Friadent DPS (grit blasted/acid etched), experimental surface (grit blasted/acid etched/neutralised), TPS (titanium plasma sprayed); Straumann SLA (grit blasted/acid etched); 3i Osseotite (acid etched); Nobel Biocare TiUnite (anodised) and Mk III (machined). (1) One implant of each type was exposed to a suspension of rat calvarial osteoblasts for 30 minutes (4 separate experiments). Cells were classified by SEM into four stages of attachment. Numbers at each stage were expressed as percentages of the total counted on each implant and results analysed by ANOVA. (2) In an organ culture model of osseointegration, 3 implants of each type were cultured in contact with rat calvarial bone fragments for 2 or 4 weeks, followed by SEM comparison of cell migration, proliferation, morphology and production of extracellular matrix (ecm).
Results: Cells spread significantly more rapidly on the experimental and SLA surfaces compared with all others except TPS. No differences were seen in percentages of cells at any stage on SLA and experimental surfaces. Relatively fewer fully spread (stage 4) cells were seen on DPS (smooth microstructure) compared with new surface (porous microstructure) implants of similar surface roughness. On the latter, several stage 4 cells were characteristically extended via formation of widespread multifocal connections to the surface structures. In organ cultures, cell-microstructure interactions were generally correlated with cell appearances in suspension assays. Cells migrated and proliferated on all implants forming multicellular layers and cell bridges. Ecm was seen on surfaces and between cells after 2 weeks on all implants.
Conclusions: Surface microstructure influenced cell spreading on the commercial implant surfaces. The experimental surface promoted rapid cell spreading, and permitted osteoblast proliferation and ecm production, consistent with differentiation.