title: Guided bone regeneration may be negatively influenced by nicotine administration: a histologic study in dogs.
abstract: BACKGROUND
  A series of animal and in vitro data confirms that nicotine impairs bone healing, diminishes osteoblast function, and causes autogenous bone graft morbidity. Therefore, this study aimed to investigate the impact of nicotine on the healing of bone defects treated by the guided bone regeneration (GBR) principle.
  
  
  METHODS
  Sixteen mongrel dogs were used. One defect was surgically created bilaterally and randomly assigned as an expanded polytetrafluoroethylene (ePTFE) membrane site or a non-membrane control site. The animals were randomly assigned to one of the following groups: group 1, placebo (n = 8) and group 2, subcutaneous administration of nicotine (2 mg/kg) twice daily (n = 8). After 4 months, the animals were sacrificed and the specimens routinely processed for semi-serial decalcified sections. The evaluated parameters were bone height, bone width, bone density, and bone area of newly formed bone.
  
  
  RESULTS
  Intergroup analysis (Kruskal-Wallis) showed that membrane-protected defects in the placebo group demonstrated an increased bone area when compared to membrane-protected defects in the nicotine group and non-membrane sites, regardless of nicotine administration (P < 0.05). In addition, nicotine administration significantly affected bone density in membrane- and non-membrane-protected sites (P < 0.05).
  
  
  CONCLUSIONS
  Within the limits of the present study, nicotine might affect, but not prevent, bone healing in defects treated by guided bone regeneration. The mechanisms of this effect should be investigated further.
authors.affiliation: Department of Prosthodontics and Periodontics, Division of Periodontics, School of Dentistry at Piracicaba, University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Juliana B
authors.initials: JB
authors.lastname: Saldanha
authors.forename: Suzana P
authors.initials: SP
authors.lastname: Pimentel
authors.forename: Marcio Z
authors.initials: MZ
authors.lastname: Casati
authors.forename: Enilson A
authors.initials: EA
authors.lastname: Sallum
authors.forename: Deise
authors.initials: D
authors.lastname: Barbieri
authors.forename: Heitor Júnior
authors.initials: HJ
authors.lastname: Moreno
authors.forename: Francisco H Júnior
authors.initials: FH
authors.lastname: Nociti
mesh_terms: D016301:Alveolar Bone Loss / Q000601:surgery; D000704:Analysis of Variance; D000818:Animals; D015519:Bone Density / Q000187:drug effects; D001861:Bone Regeneration / Q000187:drug effects*; D016025:Bone Transplantation; D004285:Dogs; D016557:Guided Tissue Regeneration, Periodontal; D008567:Membranes, Artificial; D009538:Nicotine / Q000009:adverse effects* / Q000097:blood; D011897:Random Allocation; D018709:Statistics, Nonparametric
chemical_list: D008567:Membranes, Artificial; D009538:Nicotine