Adhesion of human osteoblasts to titanium: A morpho-functional analysis with confocal microscopy

Area of Science:

• Biomaterials Science
• Cell Biology
• Orthopedic Research

Background:

• Implant surface properties critically influence osteoblast interactions and osseointegration outcomes.
• Understanding early cell-material interactions is key to improving dental and orthopedic implant success.

Purpose of the Study:

• To compare the in vitro adhesion and morpho-functional characteristics of human osteoblasts on titanium disks with different surface topographies.
• To evaluate the impact of Soft-SLA (sand-blasted with ZrO2/acid-etched) and Hard-SLA (sand-blasted with Al2O3/acid-etched) surfaces versus a smooth surface (SS) on osteoblast behavior.

Main Methods:

• Human osteoblasts were seeded onto SS, S-SLA, and H-SLA titanium surfaces.
• Confocal microscopy was used to assess cell shape, mitochondrial activity (living cells), and beta1-integrin/actin organization (fixed cells) at 6h and 24h.
• Cell adhesion, spreading, and proliferation were monitored over several days.

Main Results:

• No cytotoxic effects were observed on any surface.
• At 6h, osteoblasts exhibited faster and more organized adhesion on S-SLA compared to H-SLA, with wider spreading and more extended protrusions.
• S-SLA and SS surfaces supported greater osteoblast proliferation over three days compared to H-SLA, although cell morphology differed (polygonal on S-SLA, elongated on SS).

Conclusions:

• Surface preparation significantly affects early osteoblast adhesion kinetics and subsequent proliferation.
• The Soft-SLA surface demonstrates superior performance in promoting osteoblast adhesion and proliferation compared to Hard-SLA.
• Early cell spreading and organization on S-SLA and SS surfaces correlate with enhanced proliferation, with S-SLA morphology being more indicative of osteogenic potential than the fibroblast-like morphology on SS.