Clinical expression of TNF-α in smoking-associated periodontal disease

The level of TNF-alpha in gingival crevicular fluid (GCF) was analyzed with respect to smoking in patients with untreated moderate to severe periodontal disease including 30 current smokers, 19 former smokers and 29 non-smokers, in the age range 31-79 years. Concomitantly the occurrence of the periopathogens Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg) and Prevotella intermedia (Pi) and the GCF levels of albumin, IgA and IgG were analyzed. With regard to clinical characteristics, there were no statistically significant differences between smoking groups. The occurrence of patients positive for the periopathogens Aa, Pg and Pi was 28.2%, 41.0% and 91.0%, respectively. There were no statistically significant differences between smoking groups with regard to occurrence or relative frequency of these periopathogens. An exception was a significantly lower occurrence of Aa in former smokers as compared to non-smokers. The chief novelty of the study was the observation of a clearly increased level of TNF-alpha in GCF associated with smoking. Both current and former smokers exhibited significantly higher levels of TNF-alpha in comparison to nonsmokers, whereas the levels of albumin, IgA and IgG were the same irrespective of smoking. In conclusion, the present observations in patients with moderate to severe periodontal disease suggest that smoking is associated with elevated GCF levels of the cytokine TNF-alpha.