Locally released dexamethasone and its effects on osteogenic activity at implant-tissue interface

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Orthopedic Implants

Background:

• Osseointegration of titanium implants is critical for therapeutic success.
• Functional coatings enhance implant bioactivity and treatment outcomes.
• Chitosan microspheres offer a promising platform for drug delivery at the tissue-implant interface.

Purpose of the Study:

• To enhance the bioactivity of titanium implants by coating them with dexamethasone (DEX)-loaded chitosan microspheres.
• To investigate the effect of DEX-loaded chitosan microspheres on osteogenic differentiation and mineralization of titanium surfaces.
• To evaluate the drug loading efficiency and release profile of DEX from chitosan microspheres.

Main Methods:

• Chitosan microspheres were synthesized and loaded with dexamethasone (DEX) via diffusion.
• Drug loading efficiency and release kinetics were quantified.
• Human osteosarcoma (SAOS-2) cells were cultured on coated titanium surfaces.
• Cell proliferation, mineralization (Von Kossa staining), and alkaline phosphatase (ALP) activity were assessed.

Main Results:

• Chitosan microspheres achieved approximately 50.2% DEX loading efficiency.
• DEX release occurred over 24 hours, with 32.6% released.
• DEX-loaded coatings initially showed lower cell proliferation, followed by increased proliferation on day 7.
• Mineralization was observed by day 14, particularly in DEX-loaded samples.
• ALP activity indicated DEX influenced osteogenic differentiation, peaking on day 7.

Conclusions:

• DEX-loaded chitosan microspheres effectively enhance osteogenic differentiation and mineralization on titanium surfaces.
• The functionalized coating improves the biocompatibility and bioactivity of titanium implant materials.
• This approach holds promise for improving osseointegration and clinical outcomes of orthopedic implants.