Clinical effect of smoking on the healing response following scaling and root planing

Previous studies have suggested that cigarette smoking is a significant risk factor for periodontal diseases. 1-3 Compared to non-smokers, smokers have a higher prevalence for periodontitis, a greater extent of periodontal diseases and rate of disease progression. Cigarette smoking has been related to progressive loss of periodontal attachment, 3 increasing probing depth, 2,3 alveolar bone loss.In addition, both non-surgical and surgical periodontal treatments appear to be less effective in smokers than non-smokers. Previous studies have shown that smokers demonstrated a less favorable treatment response than non-smokers for pocket reduction and resolution of gingival inflammation. Treatments in smokers resulted in lesser probing depth reduction and smaller clinical attachment level gain. 1) Cigarette smoke contains numerous toxic substances, some of which have been shown to alter host defense and repair mechanisms by adversely affecting normal polymorphonuclear leukocyte functions, such as chemotaxis and phagocytosis, as well as increasing the release of superoxide and H2O2 by neutrophils. 17 Further, decreased levels of serum IgG, IgA and IgM, yet increased levels of IgE in smokers may also contribute to compromised healing mechanisms. Cigarette smoking has also been demonstrated to increase the risk of subgingival infection with periodontal pathogens by modulating the subgingval microbial ecology.