Clinical and microbiological effect of probiotics and antibiotics in treatment of periodontitis

OBJECTIVE: The objective of this study was to evaluate clinical and microbiological effects of Lactobacillus rhamnosus SP1- containing probiotic and azithromycin as an adjunct treatment to periodontal therapy for chronic periodontitis patients (NCT02839408, clinicaltrials.gov)   METHOD: A randomized placebo- controlled clinical trial was conducted. Fifty-six chronic periodontitis patients were recruited and monitored clinically at baseline, 3 and 6 months after scaling and root planing (SRP). Examination consisted of full mouth probing pocket depth (PPD), gingival recession, clinical attachment level, plaque index and bleeding on probing, measured at six sites per tooth. Microbiological sampling was performed at baseline, 3 and 6 months after SRP.  All patients received SRP and were randomly assigned to a probiotic (SRP+ L. rhamnosus SP1, n=19), antibiotic (SRP+ Azithromycin, n=19) or control (SRP+ placebo, n=18) group. Powder for oral suspension containing L. rhamnosus SP1 was used once a day for 3 months. Azithromycin (500mg) was used once a day for 5 days. All subjects received supportive periodontal therapy every 3 months. The primary outcome variable was change in PPD.  Wilcoxon signed Rank test and Fisher’s exact test were used to evaluate intra- group differences. ANOVA test, Bonferroni post hoc test, Kruskal Wallis test and Dunn’s test were used to evaluate inter- group differences.   RESULTS: No statistically significant differences were observed between groups for any parameters evaluated at baseline and 6 months follow- up.  Therapies equally reduced clinical parameters at 6 months after SRP. PPD reduction in probiotic group was -0.5 ± 0.3mm (p=0.0015), antibiotic group, -0.7 ± 0.5 (p=0.0009) and placebo group, -0.5 ± 0.4mm (p=0.0017). There was a significant reduction in total subgingival microbiota in probiotic (p=0.0002) and placebo (p=0.0185) groups at 6 months after SRP. All patients entering the study completed it. Adverse event was reported by only one subject from the antibiotic group.   CONCLUSION: Oral administration of L. rhamnosus SP1 and azithromycin generate similar clinical results to SRP alone. Adjunctive systemic probiotic provides small additional benefit in terms of reductions in total subgingival microbiota in comparison with the use of antibiotics.