title: Effects of tobacco products on the attachment and growth of periodontal ligament fibroblasts.
abstract: BACKGROUND
  Cigarette smoking is one of the most significant risk factors in the development and further advancement of inflammatory periodontal disease, however, the role of either nicotine or its primary metabolite cotinine in the progression of periodontitis is unclear. This study aimed to investigate the effects of nicotine and cotinine on the attachment and growth of fibroblasts derived from human periodontal ligament (PDL).
  
  
  METHODS
  Primary cultures were prepared from the roots of extracted premolar teeth. Cells were used at both low (P3 to P5) and high (P11 to P13) passage. Cell numbers were determined over 14 days using either the 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay or with a Coulter counter. Cultures were exposed to culture medium supplemented with 1) 15% fetal calf serum (FCS) only; 2) 1% FCS only; 3) 1% FCS and nicotine (concentration range 5 ng/ml to 10 mg/ml); or 4) 1% FCS and cotinine (concentration range 0.5 ng/ml to 10 microg/ml).
  
  
  RESULTS
  Nicotine significantly (P <0.05, by ANOVA) inhibits attachment and growth of low passage cells at concentrations >1 mg/ml and high passage PDL fibroblasts at concentrations >0.5 mg/ml. Cotinine, at the highest concentration used (10 microg/ml), appeared to inhibit attachment and growth of both low and high passage fibroblasts but this was not statistically significant (P >0.05, by ANOVA).
  
  
  CONCLUSIONS
  Tobacco products inhibit attachment and growth of human PDL fibroblasts. This may partly explain the role of these substances in the progression of periodontitis.
authors.affiliation: Department of Dental Medicine and Surgery, Turner Dental School, University of Manchester, UK.
authors.forename: J A
authors.initials: JA
authors.lastname: James
authors.forename: N M
authors.initials: NM
authors.lastname: Sayers
authors.forename: D B
authors.initials: DB
authors.lastname: Drucker
authors.forename: P S
authors.initials: PS
authors.lastname: Hull
mesh_terms: D000704:Analysis of Variance; D002448:Cell Adhesion / Q000187:drug effects; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004396:Coloring Agents; D003367:Cotinine / Q000494:pharmacology*; D003470:Culture Media; D018450:Disease Progression; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D009538:Nicotine / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000494:pharmacology*; D010513:Periodontal Ligament / Q000166:cytology / Q000187:drug effects*; D010518:Periodontitis / Q000209:etiology / Q000503:physiopathology; D010947:Plants, Toxic; D012907:Smoking / Q000009:adverse effects; D013778:Tetrazolium Salts; D013844:Thiazoles; D014026:Nicotiana
chemical_list: D004396:Coloring Agents; D003470:Culture Media; D018722:Nicotinic Agonists; D013778:Tetrazolium Salts; D013844:Thiazoles; D009538:Nicotine; C022616:thiazolyl blue; D003367:Cotinine