Induced osteogenesis by chitosan (3-glycidoxypropyl)trimethoxysilane and silica based biomaterial in rabbits

Synthetic biomaterials obtained through tissue engineering offer an alternative to the use of autologous and heterologous grafts for the repair of bone defects of various etiologies, although the ideal material for this purpose has not yet been developed. A gel based on Chitosan (CS) ((3-glycidoxypropyl)trimethoxysilane (GPTMS), and silica have shown efficacy in experimental studies from a biomechanical and in vitro osseointegration perspective.

To demonstrate that the hybrid aerogel based on CS-GPTMS-silica is effective and safe for treating bone defects in load-bearing bone in rabbits.

A comparative experimental study was conducted on 12 adult New Zealand rabbits, involving osteotomy in both radii as case (osteotomy with biomaterial placement) and contralateral control (osteotomy with placement of the extracted bone), both fixed with plates and screws. After 10 weeks, the animals were euthanized, and the surgical area was subjected to histological analysis.

For all subjects, wound healing was successful, and normal gait was observed within 24-48hours. In case limbs, cortical closure of 95.9% was observed compared to 98% in control limbs. Residual biomaterial was observed in 5 subjects, with an average of 16% of the total analyzed area. Inflammatory cells were grouped (5-10%) in all case samples, with significant differences between case and control samples (P<.05). An increase in the presence of bone precursor cells (5-10%) was observed in all case samples compared to control samples, with significant differences (P<.05).

The aerogel based on chitosan CS-GPTMS, and silica is biocompatible and safe in rabbits, demonstrating minimal inflammatory reaction, good osteoblast adhesion, and a high resorption rate.