The effect of nicotine on distraction osteogenesis: an experimental study on rabbits.

Background: Tobacco smoke contains more than 4,000 constituents, but not all of them are reported to have adverse effects on bone healing after distraction osteogenesis. No research on the systemic administration of nicotine has been done on distraction osteogenesis of the weight-bearing long bones of the lower extremity.

Methods: Fourteen New Zealand white male rabbits underwent distraction osteogenesis on the right tibia and lengthening by 1 cm. Transdermal nicotine bands were applied onto the dorsal skin of the rabbits in the study group. Mineral density of the distraction zone was measured at weekly intervals using quantitative computerized tomography. Mechanical properties were assessed by torsional loading, and the regenerated bone tissue was subjected to histopathological examination.

Results: Comparisons of weekly measurements in both groups showed that while the increase in bone density in the nicotine group was higher, relative to the initial values, it was still far behind the average density obtained in the control group at the end of the experiment. Statistical analysis of mechanical data showed significant differences in the gradient of the regression lines and maximum torsional angles between the two groups. The histopathological assessments showed noticeable neovascularization in the study group, which was concluded to be a compensatory mechanism for the negative delaying effect of nicotine on bone healing.

Conclusion: Systemic administration of nicotine can cause delays in the process of healing in distraction osteogenesis by its negative effect on the mineralization of the regenerate. Patients should be made aware of this negative impact of nicotine before the limb-lengthening surgery.