The Effects of Surface Patterning and Photobiomodulation on the Osseointegration of Titanium Implants in Osteoporotic Long Bones: An In Vivo Study in Rats

Abstract

This study aimed to assess the impact of titanium surface patterning used in combination with photobiomodulation therapy on enhancing osseointegration in osteoporotic bone fractures. C.p. titanium implants were employed, half with an unmodified surface and half with a modified one, showing a nanostructured cellular surface. Surface patterning aimed to obtain a complex morphology designed for better osseointegration, using a selective anodization process after photoresist coating. A total of 52 rats were used, of which 4 were sacrificed 12 weeks after ovariectomy to evaluate bone density. A total of 48 rats received titanium implants in both tibiae and underwent surgery for implant placement and bone fracture. Half of the rats were subjected to photobiomodulation. The times of sacrifice were 2, 4, and 6 weeks after finalizing LASER therapy. The evaluation methods were micro-CT scanning, the mechanical pull-force test, and morphology. Mechanical tests revealed a significant difference in the surface-patterned titanium with the LASER group at 2 weeks, but not at 4 and 6 weeks. This group outperformed regular titanium and titanium/LASER groups. Micro-CT showed no significant differences, while the morphology indicated better bone quality at 4 weeks in all LASER-treated groups. The effect of surface patterning and photobiomodulation leads to better osseointegration, especially in the earlier stages.

Keywords

• surface-patterned titanium implants
• photobiomodulation
• osteoporosis
• LASER therapy