Evaluation of the clinical and immunomodulatory effects of the probiotic lozenges or sub-antimicrobial dose doxycycline as adjuncts to non-surgical periodontal therapy in chronic periodontitis

The effect of probiotics or sub-antimicrobial dose doxycycline (SDD) as an adjunct to scaling and root planing (SRP) on inflammatory parameters in chronic periodontitis (CP) patients needs further investigation because of the controversial data. Therefore, the aim of the present study was to evaluate the clinical and immunomodulatory efficacy of Lactobacillus reuteri (L. reuteri) containing lozenges (Probiotic) or SDD (Doxycycline hyclate) as adjuncts to non-surgical periodontal therapy. A total of 45 patients, with at least 2 teeth having one approximal site with a probing depth (PD) of 5-7 mm and gingival index (GI) of ≥2 in each quadrant, were selected and randomly divided into 3 groups. Group I received SRP + Probiotic lozenges (2x108 cfu/ml), Group II received SRP + SDD (doxycycline hyclate) tablets, whereas Group III received SRP + placebo. Plaque index (PI), GI, PD, bleeding on probing (BoP) and attachment gain were measured and gingival crevicular fluid (GCF) sampling was performed at baseline and day 90. GCF analysis were assessed by enzyme linked immunosorbent assay (ELISA). GCF volume, MMP-8 and TIMP-1 levels were also evaluated at baseline and at day 90. Intra-group comparisons of all parameters were evaluated with paired sample t test while inter-group comparisons of all clinical and biochemical parameters were evaluated with Oneway Anova test. Tukey test was used for the double comparisons of the groups. The statistical significance was set at p <0.05. At the end of the observation period, statistically significant improvements in all evaluated parameters were observed within each group. Inter- group comparisons of mean differences of both clinical and biochemical parameters revealed statistically significance in favour of both SRP + Probiotic and SRP + SDD between days 0-90 at the end of day 90 (p< 0.05). However, no siginificant differences were observed between SRP + Probiotic and SRP + SDD in terms of both clinical and biochemical parameters. (p> 0.05) In conclusion, the results of the present study revealed that the adjunctive usage of L. reuteri containing lozenges and SDD tablets significantly reduced inflammation when compared to SRP + placebo in CP patients.