Carbon nanotube‑ and hydroxyapatite‑coated implants: histomorphometric assessment in a rabbit model

Objective This study aimed to investigate whether the integration of functionalized carbon nanotubes (CNTs) with hydroxyapatite (HA) could create a bioactive nanocomposite capable of enhancing the early stages of osseointegration. Specifically, we investigated whether the high surface area and nanoscale structure of CNTs, combined with the osteoconductivity of 1% HA, could significantly enhance bone-to-implant contact (BIC) and new bone area (NBA) compared to traditional titanium surfaces in a mandibular model. Methods Here we evaluated the osseointegration of titanium implant discs coated with CNTs and CNTs combined with 1% HA in a rabbit mandibular model. Thirty rabbits received uncoated, CNT-coated, or CNT- HA coated titanium discs implanted into mandibular defects. After 4 weeks, bone-to-implant contact (BIC) and new bone area (NBA) were assessed histomorphometrically. Results Both CNT and CNT- HA coatings significantly increased BIC and NBA compared to uncoated implants ( p < 0.05), with no significant difference between coated groups. Conclusion CNT-based coatings enhance early osseointegration of titanium implants, while the addition of 1% HA does not confer additional benefit within 4 weeks, suggesting CNT coatings alone may improve implant integration effectively.