In-situ Damascus-patterning enables tunable surface electric fields for bioactive titanium implants

Area of Science:

• Biomaterials Engineering
• Orthopedic Implants
• Surface Science

Background:

• Conventional titanium implants are biocompatible but bioinert, necessitating surface modifications for effective osseointegration.
• Achieving satisfactory osseointegration with current titanium implants often requires complex surface treatments.

Purpose of the Study:

• To develop an additive manufacturing strategy for imparting bioactivity directly to titanium-tantalum implants.
• To create implants with tunable periodic surface potential differences (P-SPD) for enhanced biological response.

Main Methods:

• Utilized laser powder bed fusion to create titanium-tantalum implants with in situ compositional modulation.
• Generated Damascus-like patterns through controlled tantalum melting into the titanium matrix.
• Oxidized the patterned implants to produce stable, tunable P-SPD.

Main Results:

• Achieved tunable P-SPD ranging from 5.59 to 48.01 mV, mimicking natural tissue electric fields.
• The generated electric field (∼2.35 V/m) promoted osteogenesis, cell migration, and neural responses.
• Demonstrated nearly doubled osteogenic performance in vitro and in vivo cranial defect repair compared to controls.

Conclusions:

• Additive manufacturing enables in situ integration of structural and biological functions in high-performance titanium-tantalum implants.
• The P-SPD generated by Damascus-like patterns significantly enhances osseointegration and bone regeneration.
• This approach offers a novel paradigm for bioimplant surface functionalization.