Can probiotic supplements prevent early childhood caries? A systematic review and meta-analysis.

The aim of this study was to explore the preventive effect of probiotic supplements on the development of early childhood caries (ECC). We searched the PubMed, Google Scholar and Cochrane databases up to January 15, 2021. The authors screened the hits independently for relevance, extracted outcome data and assessed the risk of bias. We performed a random effects meta-analysis to pool and compare the incidence of ECC in children assigned to test or placebo groups, respectively. The authors included nine randomised controlled trials published between 2001 and 2021, involving 2,363 preschool children. We assessed two publications with a moderate risk of bias and seven with high risk of bias. The median caries incidence in the probiotic test groups was 8.5% compared with 17.5% in the placebo groups and this difference was statistically significant (P<0.001). A pooled random effects meta-analysis on caries incidence on subject level showed a small but statistically significant risk difference in favour of the probiotic intervention (-0.05, 95% confidence interval (CI) -0.10, -0.00; P<0.05). The mean difference in caries increment on tooth/surface level was -0.57, (95% CI -0.91, -0.23; P<0.01). In conclusion, we demonstrated a small but statistically significant preventive effect of probiotic supplements on ECC. However, the certainty of this finding was low due to the risk of bias, heterogeneity and inconsistencies across the studies. Further long-term randomised controlled trials with low risk of bias are required in order to answer the research question with a higher certainty.

A systematic review of risk assessment tools for early childhood caries: is there evidence?

AIM: To evaluate the accuracy of commonly advocated caries risk assessment (CRA) tools in preschool children and to search for evidence whether or not this process provides better oral care and less caries in the future. METHODS: As an update of a previous systematic review, a search of electronic databases for relevant literature published between 2008 and 2018 was performed with aid of predetermined search strings. We considered only true prospective trials validating baseline risk categories over at least a 12-month period, and extracted the predictive values and assessed the quality of the papers by the QUIPS tool for prospective studies. RESULTS: Six studies were included, reporting on three manual checklists and two software tools. The National University of Singapore model displayed a good accuracy in two studies, while the accuracy of Cariogram ranged from poor to good in various populations. The manual checklists were only validated in one study each and displayed limited to poor accuracy. No study was identified that addressed questions around the long-term benefits of CRA. CONCLUSIONS: This systematic review showed a relative paucity of prospective trials validating the existing caries risk assessment tools in preschool children and the question whether or not the CRA process results in better oral care remained unanswered. Although the accuracy was far from excellent, we still recommend the CRA tools in paediatric dentistry practice because the desirable effects most likely outweigh the undesirable effects.

Presence of Lactobacillus reuteri in saliva coincide with higher salivary IgA in young adults after intake of probiotic lozenges.

The aim of this study was to compare the concentration of salivary immunoglobulin A (IgA) and the selected interleukins (IL)-1ß, IL-6, IL-8 and IL-10 in young individuals with presence and non-presence of Lactobacillus reuteri in saliva after a three-week intervention with probiotic lozenges. The study group consisted of 47 healthy individuals aged 18-32 years with no clinical signs of oral inflammation. In a randomised, double-blind, placebo-controlled, cross-over trial participants ingested two lozenges per day containing two strains of the probiotic bacterium L. reuteri or placebo lozenges. The intervention and wash-out periods were three weeks. Stimulated and unstimulated whole saliva was collected at baseline and immediately after termination of the intervention periods. The samples were analysed for total protein, salivary IgA and selected cytokines. In this extended analysis, data were collected by analysing baseline and follow-up saliva samples related to ingestion of the probiotic lozenges for the presence of L. reuteri through DNA-extraction, PCR-amplification and gel-electrophoresis. At baseline, 27% of the individuals displayed presence of L. reuteri and 42% were positive immediately after the three-week probiotic intervention. Individuals with presence of L. reuteri in saliva had significantly higher (P<0.05) concentrations of salivary IgA and %IgA/protein at the termination of the probiotic intake compared with non-presence. No differences in the cytokine levels were observed. In conclusion, detectable levels of L. reuteri in saliva coincided with higher concentrations of salivary IgA and %IgA/protein in stimulated whole saliva after the three-week daily intake of probiotic lozenges. Our findings suggest that monitoring the presence of probiotic candidates in the oral environment is important to interpret and understand their possible immune-modulating role in maintaining oral health.

Effect of Probiotic Bacteria on Oral Candida in Frail Elderly.

The aim of this study was to investigate the effect of a daily intake of probiotic lactobacilli on the prevalence and counts of oral Candida in frail elderly patients living in nursing homes. The study had a double-blind randomized placebo-controlled design with 2 parallel arms. The study group consisted of 215 older adults (range, 60 to 102 y) who were enrolled after informed consent. After baseline examination and randomization, the subjects were given 1 lozenge containing 2 strains of the probiotic bacterium Lactobacillus reuteri (DSM 17938 and ATCC PTA 5289) or placebo twice daily (morning and evening). The intervention period was 12 wk, and saliva and plaque samples were collected at baseline and follow-up. The primary end point was prevalence of high Candida counts assessed from chairside tests. Secondary end points were levels of dental plaque and gingival inflammation. The groups were balanced at baseline. The attrition rate to follow-up was 19%. There was a statistically significant reduction in the prevalence of high Candida counts in the probiotic group but not in the placebo group, and the difference was statistically significant in both saliva and plaque (P < 0.05). No significant differences between the groups were noted concerning the levels of supragingival plaque or bleeding on probing. Thus, daily use of probiotic lozenges may reduce the prevalence of high oral Candida counts in frail elderly nursing homes residents (ClinicalTrials.gov NCT02391532).