Clinical efficacy of Lactobacillus reuteri-containing lozenges in the supportive therapy of generalized periodontitis stage III and IV, grade C: 1-year results of a double-blind randomized placebo-controlled pilot study.

The aim of this 12-month mono-centre double-blind randomized placebo-controlled clinical study was to evaluate the efficacy of Lactobacillus reuteri-containing lozenges during the supportive therapy of generalized periodontitis stage III and IV, grade C (GPIII-IVC) patients. Twenty treated GPIII-IVC patients were randomly divided into 2 groups. The test group received two 3-month-long administrations of L. reuteri (2 lozenges/day after brushing) with a 3-month washout period, while the control one received a placebo. Outcome measures were tooth survival, complications and adverse events, change in probing pockets depth (PPD), change in probing attachment level (PAL), presence of bleeding on probing (BOP) and patient's evaluation of treatment. Measurements were collected at 3, 6, 9 and 12 months. At 1 year, no dropout, tooth loss, complications or adverse event were recorded. Mean PPD and mean PAL and percentages of sites with BOP were statistically improved (p < 0.05) compared with baseline in both groups, while more PPD reduction at all time points (p < 0.05) and more PAL gain at 6 months and more BOP reduction at 6 and 9 months were found in the probiotic group (p < 0.05). Within the limitation of the study, the use of L. reuteri probiotics lozenges improved some clinical outcomes in treated GPIII-IVC patients during maintenance therapy. Studies with a larger number of patients are needed to confirm these data. The use of L. reuteri probiotic lozenges could be considered as an adjunct in the maintenance therapy of GPIII-IVC patients.