Efficacy of probiotics against dental caries in children: a systematic review and meta-analysis

Probiotics-containing beverages and dental caries: A systematic review and meta-analysis

The aim was to evaluate the effect of probiotics-containing beverages on dental caries development by a systematic review and meta-analysis (PROSPERO CRD42021258010). PubMed, Embase, and Web of Science databases were assessed (up to October 2023) for randomized placebo-controlled trials that evaluated the consumption of probiotics-containing beverages having dental caries as endpoint. Risk of bias assessment (Cochrane Handbook) was performed for all studies. Risk ratio (RR), standardized mean difference (SMD) and 95% confidence interval (CI), were calculated for caries prevalence and caries increment, respectively. Meta-analysis was performed. Qualitative analysis of more than 2000 individuals aged from 1 to 84 years (9 studies) showed inconsistent effects of these probiotics-containing beverages. Synthesis of more than 1000 children and adolescents did not demonstrate a statistically significant difference in the proportion of individuals with cavitated lesions (RR 0.60 [95 % CI 0.34 to 1.08]; n = 2), but a significantly smaller increment of both cavitated and non-cavitated carious lesions (SMD -0.23 [95 % CI -0.39 to -0.08]; n = 4) was related to the consumption of probiotics-containing beverages. Certainty of evidence for caries prevalence and caries increment were moderate and low, respectively. Current evidence is not substantial to strengthen the impact of these beverages on caries development.

Effect of Probiotic Supplements on the Oral Microbiota-A Narrative Review

Data from systematic reviews and meta-analyses show that probiotics positively impact clinical parameters of oral diseases such as gingivitis, dental caries, and periodontitis. However, the working mechanism of probiotics is not fully understood, but is hypothesized to be mediated by direct and indirect interactions with the oral microbiota and the human host. In the present narrative review, we focused on the microbiological effect of probiotic supplements based on data retrieved from randomized clinical trials (RCTs). In addition, we assessed to what extent contemporary molecular methods have been employed in clinical trials in the field of oral probiotics. Multiple RCTs have been performed studying the potential effect of probiotics on gingivitis, dental caries, and periodontitis, as evaluated by microbial endpoints. In general, results are conflicting, with some studies reporting a positive effect, whereas others are not able to record any effect. Major differences in terms of study designs and sample size, as well as delivery route, frequency, and duration of probiotic consumption, hamper comparison across studies. In addition, most RCTs have been performed with a limited sample size using relatively simple methods for microbial identification, such as culturing, qPCR, and DNA-DNA checkerboard, while high-throughput methods such as 16S sequencing have only been employed in a few studies. Currently, state-of-the-art molecular methods such as metagenomics, metatranscriptomics, and metaproteomics have not yet been used in RCTs in the field of probiotics. The present narrative review revealed that the effect of probiotic supplements on the oral microbiota remains largely uncovered. One important reason is that most RCTs are performed without studying the microbiological effect. To facilitate future systematic reviews and meta-analyses, an internationally agreed core outcome set for the reporting of microbial endpoints in clinical trials would be desirable. Such a standardized collection of outcomes would most likely improve the quality of probiotic research in the oral context.

Elimination of Pathogen Biofilms via Postbiotics from Lactic Acid Bacteria: A Promising Method in Food and Biomedicine

Pathogenic biofilms provide a naturally favorable barrier for microbial growth and are closely related to the virulence of pathogens. Postbiotics from lactic acid bacteria (LAB) are secondary metabolites and cellular components obtained by inactivation of fermentation broth; they have a certain inhibitory effect on all stages of pathogen biofilms. Postbiotics from LAB have drawn attention because of their high stability, safety dose parameters, and long storage period, which give them a broad application prospect in the fields of food and medicine. The mechanisms of eliminating pathogen biofilms via postbiotics from LAB mainly affect the surface adhesion, self-aggregation, virulence, and QS of pathogens influencing interspecific and intraspecific communication. However, there are some factors (preparation process and lack of target) which can limit the antibiofilm impact of postbiotics. Therefore, by using a delivery carrier and optimizing process parameters, the effect of interfering factors can be eliminated. This review summarizes the concept and characteristics of postbiotics from LAB, focusing on their preparation technology and antibiofilm effect, and the applications and limitations of postbiotics in food processing and clinical treatment are also discussed.

Anti-oral cancer properties of potential probiotic lactobacilli isolated from traditional milk, cheese, and yogurt

This study investigates the probiotic and anti-cancer effects of 21 isolated Lactobacillus strains from cheese, milk, and yogurt in Kermanshah, Iran, on oral cancer cell lines KB and OSCC. Four selected isolates (Y33, M45, C5, and C28) displayed good viability and resistance to specific antibiotics. Notably, strains C28 and Y33 exhibited the best results, showing susceptibility or semi-susceptibility to five antibiotics. Y33, with high cell surface hydrophobicity (62%), demonstrated significant anti-pathogenic activity, inhibiting the growth of tested pathogens and displaying strong adhesion to human intestinal Caco-2 cells (52%). Further assessments, including acridine orange/ethidium bromide staining and mRNA expression analysis, revealed four isolates (C5, C28, M45, and Y33) with promising probiotic properties. Particularly, Y33's protein-based extract metabolites showed dose- and time-dependent inhibition of KB and OSCC cancer cell lines, inducing apoptosis without significant cytotoxic effects on normal cells. Y33 (Lactiplantibacillus plantarum) exhibited the strongest probiotic potential, surpassing conventional anti-cancer drugs, suggesting its therapeutic potential for preventing oral cancer cell proliferation and improving survival rates in oral cancer patients.

YouTube Videos on Nutrition and Dental Caries: Content Analysis

BACKGROUND

Dental caries is the most common health condition worldwide, and nutrition and dental caries have a strong interconnected relationship. Foods and eating behaviors can be both harmful (eg, sugar) and healthful (eg, meal spacing) for dental caries. YouTube is a popular source for the public to access information. To date, there is no information available on the nutrition and dental caries content of easily accessible YouTube videos.

OBJECTIVE

This study aimed to analyze the content of YouTube videos on nutrition and dental caries.

METHODS

In total, 6 YouTube searches were conducted using keywords related to nutrition and dental caries. The first 20 videos were selected from each search. Video content was scored (17 possible points; higher scores were associated with more topics covered) by 2 individuals based on the inclusion of information regarding various foods and eating behaviors that impact dental caries risk. For each video, information on video characteristics (ie, view count, length, number of likes, number of dislikes, and video age) was captured. Videos were divided into 2 groups by view rate (views/day); differences in scores and types of nutrition messages between groups were determined using nonparametric statistics.

RESULTS

In total, 42 videos were included. Most videos were posted by or featured oral health professionals (24/42, 57%). The mean score was 4.9 (SD 3.4) out of 17 points. Videos with >30 views/day (high view rate; 20/42, 48% videos) had a trend toward a lower score (mean 4.0, SD 3.7) than videos with ≤30 views/day (low view rate; 22/42, 52%; mean 5.8, SD 3.0; P=.06), but this result was not statistically significant. Sugar was the most consistently mentioned topic in the videos (31/42, 74%). No other topics were mentioned in more than 50% of videos. Low-view rate videos were more likely to mention messaging on acidic foods and beverages (P=.04), water (P=.09), and frequency of sugar intake (P=.047) than high-view rate videos.

CONCLUSIONS

Overall, the analyzed videos had low scores for nutritional and dental caries content. This study provides insights into the messaging available on nutrition and dental caries for the public and guidance on how to make improvements in this area.