Effect of Bio Function Enhanced-Dual TiO2 Nanotube Implants on Osseointegration: A Comparative Study in Rabbit Model

Abstract

The purpose of this study is to evaluate the effect of dual TiO2 nanotube implant on osseointegration in rabbit. A dual TiO2 nanotube implant, consisting of various combinations of two different nanotube sizes, was divided into four groups: 8 nm/30 nm, 8 nm/70 nm, 30 nm/70 nm, and 30 nm/100 nm TiO2 nanotube. A total of 40 dual TiO2 nanotube implants were fabricated and implanted to the tibia of rabbits, which were then sacrificed after 2 and 12 weeks. The level of osseointegration was compared among the groups throughout the radiologic, histological, and histomorphometric analysis. The micro-CT analysis results showed that the bone volume (BV) value (%) of 12-week group was higher than that of 2-week group overall, and 8/30 group within the 2-week group and 30/100 group within the 12-week group displayed the highest BV value (p > 0.05). The histologic and histomorphometric analysis also showed that the recession (%) around the micro-thread was significantly lower in the 12-week group than in the 2-week group (p < 0.05), and 8/70 group within the 2-week group and 30/70 group and 30/100 group within the 12-week group presented the lowest value. The area of the new bone (μm2) formed above upper cortical bone border was the largest in 30/70 group within the 2-week group and in 30/100 group within the 12-week group (p > 0.05). The bone to implant contact (BIC) value (%) measured within the bone marrow exhibited that 8/30 group in the 2-week group and 8/70 group in the 12-week group had the highest (p > 0.05), while the BV value (%) measured within the marrow revealed that 30/100 groups in both of 2-week and 12-week groups had the highest (p > 0.05).