title: Saliva concentrations of RANKL and osteoprotegerin in smoker versus non-smoker chronic periodontitis patients.
abstract: OBJECTIVE
  To compare the salivary receptor activator of NF-kappaB ligand (RANKL) and osteoprotegerin (OPG) concentrations in smokers versus non-smokers with chronic periodontitis.
  
  
  METHODS
  Whole saliva samples were obtained from 67 untreated chronic periodontitis patients, of whom 34 were smokers, and from 44 maintenance patients, of whom 22 were smokers. Full-mouth clinical periodontal measurements were recorded. Saliva cotinine, sRANKL and OPG concentrations were determined by ELISA. Statistical analysis was performed using the Mann-Whitney U test, Bonferroni's correction for multiple comparisons and Spearman's correlations.
  
  
  RESULTS
  Untreated smokers exhibited significantly higher values of clinical periodontal recordings than untreated non-smokers (all p<0.05). Salivary cotinine level correlated with clinical attachment level (p=0.023). Smoker versus non-smoker maintenance groups showed no significant differences in clinical parameters. There were significant differences in sRANKL and OPG concentrations between untreated and maintenance groups (all p<0.01). Salivary OPG concentration was significantly lower (all p<0.01) and the sRANKL/OPG ratio was higher (all p<0.01) in smokers than in non-smokers. OPG concentration correlated positively with probing depth, clinical attachment level and bleeding on probing (all p<0.005) and negatively with pack-year, and cotinine level (p<0.05).
  
  
  CONCLUSIONS
  Salivary RANKL and OPG concentrations are suggested to be affected by smoking as not only the untreated but also the treated smokers exhibited higher RANKL and lower OPG concentrations than non-smokers.
authors: Department of Periodontology, School of Dentistry, Ege University, Izmir, Turkey. nurcan.buduneli@ege.edu.tr
authors: Nurcan
authors: N
authors: Buduneli
authors: Başak
authors: B
authors: Biyikoğlu
authors: Sakhr
authors: S
authors: Sherrabeh
authors: David F
authors: DF
authors: Lappin
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D055113:Chronic Periodontitis / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D053244:Osteoprotegerin / Q000378:metabolism*; D053245:RANK Ligand / Q000378:metabolism*; D012463:Saliva / Q000378:metabolism*; D012907:Smoking / Q000378:metabolism*; D018709:Statistics, Nonparametric
chemical_list: D053244:Osteoprotegerin; D053245:RANK Ligand