Effect of synbiotics in the treatment of smokers and nonsmokers with gingivitis: randomized controlled trial.

Background To evaluate the efficacy of synbiotic tablets on the clinical and biochemical parameters of smokers and non-smokers with gingivitis. Methods Eighty patients with gingivitis [40 smokers (+), 40 non-smokers (-)] were randomly assigned to test (T) or control (C) groups. Four groups were defined: T(+), T(-), C(+) and C(-). The subjects daily chewed a synbiotic or placebo tablet for 30 days. The gingival crevicular fluid levels of interleukin (IL)-6, IL-8 and IL-10 were determined as the primary outcome variables. Results The clinical and biochemical parameters for all groups significantly reduced compared with the baseline (P < 0.05). While there were no significant differences between the groups for gingival index, the plaque index was significantly higher in both smoker groups than that in the T(-) group during the second month (P < 0.05). IL-8 levels in C(-) and IL-6 levels in both control groups were significantly higher than those in the T(+) group. The IL-10 levels in both control groups were significantly higher than those in the T(-) group during the second month (P < 0.05). Conclusions Adjunctive synbiotic tablets significantly reduce subclinical therapeutic outcomes for both smokers and non-smokers compared with placebo according to the biochemical parameters.