Influence of nicotine on healing process of autogenous bone block grafts in the mandible: a histomorphometric study in rats.
OBJECTIVE
The aim of this study was to perform qualitative and quantitative analyses of the effect of nicotine on autogenous bone block grafts and to describe events in the initial healing phase and the differences in the repair processes between animals exposed to nicotine and controls.


METHODS
Forty-eight female Wistar rats were randomly divided into 2 groups, the nicotine group and the saline group. All animals received either nicotine (3 mg/kg) or saline 4 weeks before the surgical procedure and continued to receive nicotine from surgery to sacrifice at 7, 14, or 28 days. The autogenous bone block graft was harvested from the calvaria and stabilized on the external cortical area near the angle of the mandible.


RESULTS
The histologic analyses of the nicotine group depicted a delay in osteogenic activity at the bed-graft interface, as well as impairment of the organization of the granulation tissue that developed instead of blood clot. Nicotine-group specimens exhibited less bone neoformation, and the newly formed bone was poorly cellularized and vascularized. The histometric analysis revealed significantly less bone formation in the nicotine group at both 14 days (23.75% +/- 6.18% versus 51.31% +/- 8.31%) and 28 days (42.44% +/- 8.70% versus 73.00% +/- 4.99%).


CONCLUSIONS
Nicotine did jeopardize the early healing process of autogenous bone block grafts in rats but did not prevent it.
Bonfante
Samara
S
Dental School of Araçatuba, University of São Paulo, Brazil. sbonfante@uol.com.br
Bosco
Alvaro Francisco
AF
Luize
Danielle Shima
DS
de Almeida
Juliano Milanezi
JM
Cestari
Tania Mary
TM
Taga
Rumio
R
D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects*; D016025:Bone Transplantation; D005260:Female; D005731:Ganglionic Stimulants / Q000633:toxicity*; D008334:Mandible / Q000601:surgery; D009538:Nicotine / Q000633:toxicity*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D014945:Wound Healing / Q000187:drug effects*
D005731:Ganglionic Stimulants; D009538:Nicotine