title: Salivary immunoglobulin classes in Nigerian smokers with periodontitis.
abstract: OBJECTIVE
  To determine the levels of salivary immunoglobulin classes in Nigerian smokers and non-smokers with periodontitis.
  
  
  METHODS
  Sixty-nine individuals were recruited into this study after obtaining informed consent. They were subdivided into three groups that consisted of 20 (aged 46 ± 11 years) cigarette smokers with periodontitis (S+P); 24 (40 ± 12 years) smokers without periodontitis (S-P); and 25 (53 ± 11 years) non-smokers with periodontitis (NS+P). An oral and maxillofacial surgeon used radiographs for periodontal probing for the diagnosis of periodontitis. The smokers included subjects who smoked at least six cigarettes per day and all the periodontitis patients were newly diagnosed. About 5 mL of unstimulated saliva was expectorated by each subject into plain sample bottles. Salivary immunoglobulin levels were estimated using enzyme linked immunosorbent assay. Student's t test was used to determine significant differences between the means. Values of P < 0.05 were regarded as significant.
  
  
  RESULTS
  No significant differences were observed in the mean salivary levels of the immunoglobulin classes (IgG, IgA, IgM and IgE) when S+P was compared with S-P. Mean salivary levels of IgA (520.0 ± 155.1 ng/mL vs 670.0 ± 110 ng/mL, P = 0.000) and IgM (644.5 ± 160.0 ng/mL vs 791.4 ± 43.7 ng/mL, P = 0.000) were significantly lower in the S+P compared with NS+P group. Salivary IgA (570.4 ± 145.6 ng/mL vs 670.0 ± 110 ng/mL, P = 0.008) and IgM (703.1 ± 169.3 ng/mL vs 791.4 ± 43.7 ng/mL, P = 0.012) levels were significantly lower in the S-P compared with NS+P group. Only one (5%) periodontal patient had detectable levels of salivary IgE (0.20 IU/mL). Similarly, only one smoker (4.17%) had detectable levels of salivary IgE (0.04 IU/mL) and two non-smokers (9.52%) had detectable levels of IgE (0.24 IU/mL).
  
  
  CONCLUSIONS
  Our study suggests that reduced salivary IgA and IgM levels in smokers with periodontitis could enhance increased susceptibility to periodontitis.
authors.affiliation: Olatunde A Olayanju, Sheu K Rahamon, Ijeboime O Joseph, Olatunbosun G Arinola, Immunology Unit, Department of Chemical Pathology and Immunology, College of Medicine, University of Ibadan, Ibadan 100254, Nigeria.
authors.forename: Olatunde A
authors.initials: OA
authors.lastname: Olayanju
authors.forename: Sheu K
authors.initials: SK
authors.lastname: Rahamon
authors.forename: Ijeboime O
authors.initials: IO
authors.lastname: Joseph
authors.forename: Olatunbosun G
authors.initials: OG
authors.lastname: Arinola
keywords: Cigarette smoke; Immunoglobulin; Periodontitis; Saliva; Smokers