Effect of Lactobacillus brevis CD2 containing lozenges and plaque pH and cariogenic bacteria in diabetic children: a randomised clinical trial

OBJECTIVE: The short-term effect (60 days) of Lactobacillus brevis CD2 lozenges vs placebo on variables related to caries and gingivitis in type 1 diabetic children was evaluated. MATERIAL AND METHODS: Eight diabetics (4–14 years old) were assigned to two groups (n = 34 subjects each), probiotic lozenges and placebo. Stimulated saliva for microbiological analysis and plaque pH were assessed at baseline (t(0)), 30 days (t(1)), 60 days (t(2)) and in the follow-up period (90 days from baseline, t(3)). Gingival status was assessed at t(0), t(2) and t(3). Two-way ANOVA assessed differences between groups. RESULTS: In the probiotic group, Streptococcus mutans bacterial density mean scores dropped from 3.11 ± 1.13 at baseline to 1.82 ± 0.72 (t(2)) and to 2.06 ± 0.56 (t(3)), while in the placebo group, the scores were 3.09 ± 0.8 (t(0)), 2.82 ± 0.47 (t(2)) and 3.11 ± 0.43 (t(3)) (p < 0.01). Lowest and maximum pH fall increased in the probiotic group, from 5.37 ± 0.41 at baseline to 5.49 ± 0.24 at t(3) (p < 0.01) and from 1.20 ± 0.46 to 0.98 ± 0.29 (p = 0.02). Bleeding score decreased significantly in both groups, showing a statistically significant lower bleeding score at t(2) in the probiotic group (25.6%, 95% CI 21.5–32.7 vs 29.5%, 95% CI 25.2–34.9, p = 0.02). CONCLUSIONS: Lactobacillus brevis CD2 has shown to improve caries-related risk factors and gingival health in diabetic children. CLINICAL RELEVANCE: Lactobacillus brevis CD2 might contribute to improved oral health in type 1 diabetic children. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00784-020-03342-0) contains supplementary material, which is available to authorized users.