Influence of nicotine and implant surface on osseointegration in rabbits

Objectives: The aim of this study was to evaluate two factors that may interfere in the osseointegration process: the use of nicotine and the surface of dental implants. Methods: Twenty-two rabbits (Oryctolagus cuniculus) were randomly distributed in two groups. The right and the left tibias received machined (MACH) and anodized (ANOD) dental implants, respectively. Eleven animals received subcutaneous injection of nicotine 3mg/dia/kg (NICO), three times a day. The control group (CONT) received subcutaneous solution of 0.9% NaCl 3mL/day/kg, three times a day. After eight weeks, the animals were killed and blood samples were obtained in order to dose nicotine and cotinine. In addition, alkaline phosphatase, biomechanical and densitometry analysis were carried out in the tibia samples. Results: The plasmatic levels of nicotine and cotitine were 0.5 ± 0.28 ng/mL and 9.5 ± 6.51 ng/mL, respectively. None statistically significant differences (p=0.402) were observed between alkaline phosphatase levels of NICO (ANOD and MACH = 37.9 ± 4.84 UI/L) and CONT (MACH = 40.8 ± 11.88 UI/L; ANOD = 40.75 ± 12.46 UI/L). ANOD and MACH also did not show statistically significant differences (p=0.999). The counter-torque did not show statistically significant differences between ANOD (CONT = 25.0 ± 8.46; NICO = 38.3 ± 13.52) and MACH (CONT = 31.2 ± 6.76; NICO = 35.5 ± 14.17), however, NICO showed higher counter-torque (p=0.027) than CONT. The optical density showed no statistically significant differences (p=0.590) between NICO (MACH = 109.2 ± 32.01 Ncm; ANOD = 94.2 ± 30.25 Ncm) and CONT (MACH = 105.0 ± 28.78 Ncm; ANOD = 86.4 ± 33.96 Ncm) and between MACH and ANOD (p=0.135). Conclusion: that low doses of nicotine did not cause deleterious effects in the osseointegration of dental implants. The surface of the dental implants did not influence the parameters studied.