Oral probiotics—good bacteria instead of mouthwash?

Aim of the study: Halitosis is defined as a foul odour emitted from the oral cavity. Many interventions have been used to control halitosis from mouthwashes to chewing gums. Probiotics have been reported as an alternative method to alleviate halitosis. The present study aimed to investigate the effect of probiotics on halitosis from a time perspective.

Results: The standardised mean difference (SMD) and 95% CI were calculated to synthesise data. The data were subgrouped and analysed in the short term (≤4 weeks) and long term (>4 weeks) based on the follow-up time. Seven articles were included in this meta-analysis. The primary outcomes, OLP scores (SMD=-0.58; 95% CI -0.87 to -0.30, p<0.0001) and VSC levels (SMD=-0.26; 95% CI -0.51 to -0.01, p=0.04), both decreased significantly in the probiotics group compared with the placebo group in the short term. However, a significant reduction was observed only in OLP scores (SMD=-0.45; 95% CI -0.85 to -0.04, p=0.03) in the long term. No significant differences were observed in secondary outcomes. There was no evidence of publication bias. The leave-one-out analysis confirmed that the pooled estimate was stable.

Aim of the study: Halitosis, characterized by volatile sulfur compound (VSC) production, is a prevalent oral health concern affecting 31.8% of the global population. Conventional treatments such as chlorhexidine-based mouthwashes offer temporary relief, but probiotics have emerged as a promising biological therapy by modulating oral microbiota.

Results: Six RCTs (n = 360 participants) met the inclusion criteria. Five studies demonstrated significant VSC reduction after probiotic intervention (P < 0.05). Three studies reported OLT score improvements, particularly with Streptococcus salivarius K12 and Weissella cibaria. Four studies confirmed microbiome alterations, with the effects of probiotics persisting post-treatment. No serious adverse effects were reported. Probiotics significantly reduce VSC levels, improve OLT scores, and modulate the growth of oral microbiota. However, the heterogeneity of studies and limited long-term follow-up hinder clinical translation. Larger, standardized trials are essential for establishing the clinical efficacy. Probiotics present a safe adjunct therapy for halitosis management. Future research should focus on longitudinal studies, specific strain efficacy, and microbiome-targeted interventions.

Aim of the study: Periodontal diseases and dental caries are the two most common dental diseases caused by the dental plaque. The aim of the present study was to review the clinical efficacy of probiotics for oral health in randomized controlled trials.

Results: A total of 24 clinical trials were reviewed, including 1612 participants receiving either probiotics or mouth treatments. The results of this review indicated that individuals receiving probiotic products have a significant reduction (65% reduction; p < 0.05) in the count of Streptococcus mutants in their mouths. It was also found that probiotic products were more effective or equal in effect compared to chlorhexidine in reducing oral pathogens, gingival index, and plaque index scores. On the other hand, the consumption of xylitol mouthwash was shown to cause an improvement in salivary parameters. Considering their safety and effectiveness, the use of probiotic products, such as kefir and mouthwashes, has been recommended against cariogenic bacteria and periodontal diseases. Probiotics are considered a safe alternative to conventional therapies, such as chlorhexidine and fluoride. Co-administration of chlorhexidine, fluoride, and probiotics seems to be a perfect package.

Aim of the study: Chemical plaque control with mouthwashes as an adjunct to mechanical plaque control with a toothbrush and dental floss has been considered an effective method for controlling gingivitis. The anti-inflammatory effects of chemical plaque control benefit the oral tissues by reducing inflammation and bleeding.

Results: All groups showed a significant decrease in the MPI and BOIB scores. The results were similar in patients who used a probiotic mouthwash and those who used a CHX mouthwash. A comparable change in the mean scores was observed among the herbal and povidone-iodine groups from baseline to day 28. In the treatment of chronic gingivitis patients,a probiotic mouthwash was nearly as effective as CHX in reducing the plaque and bleeding scores. It showed better results in all clinical parameters than herbal and povidone-iodine mouthwashes. Using a mouthwash along with routine tooth brushing can help in treating gingivitis and slow the progression of the periodontal disease.

Aim of the study: Chlorhexidine is considered the most potent chemotherapeutic agent against Streptococcus mutans. However, its side effects due to prolonged use, indicates need for alternatives. The study intended to assess and compare antimicrobial efficacies of probiotic, xylitol and chlorhexidine mouth rinses in children and elderly.

Results: Significant reduction in Streptococcus mutans counts were observed in both children and elderly (Chlorhexidine: mean difference = 3.11 log10CFU/g, p = 0.022, Xylitol: mean difference = 0.93 log10CFU/g, p = 0.046, Probiotic: mean difference = 1.91 log10CFU/g, p = 0.023 in children); (Chlorhexidine: mean difference = 2.23 log10CFU/g, p = 0.004, Xylitol: mean difference = 1.39 log10CFU/g, p = 0.009, Probiotic: mean difference = 1.61 log10CFU/g, p = 0.018 in elderly). Intergroup comparison showed no significant difference. Antimicrobial efficacy of xylitol and probiotic mouth rinses were comparable to that of chlorhexidine in both children and elderly. Probiotics could potentially be more efficacious than xylitol among children.

Aim of the study: A selenium (Se) enriched Lactobacillus brevis was applied as mouthwash to relieve mouth ulcers and regulate oral pathogens. The persistence of four frequent oral pathogens (Pseudomonas, Klebsiella, Proteus, and Enterobacter) and the quantity of mouth lesions were to be measured after exposure to the above probiotic. Susceptibility of the pathogens was also examined.

Results: Klebsiella and Pseudomonas were the most frequent initial pathogens, from which Pseudomonas were totally omitted from the probiotic group. The Se-probiotic existed in the mouth cavity of the test group six hours after the last dose. In the probiotic group, the number of oral lesions were significantly reduced. Clearance of Pseudomonas from mouth cavity and significant decrease in the quantity of mouth ulcers are considerable achievements. Hence, the applied Se-supplemented mouthwash exhibited promising capability to be considered as a potential oral hygiene formulation.

Aim of the study: Background: Researchers are now focusing on new and less invasive therapies to improve the domiciliary maintenance phase of periodontitis. Ozonated olive oil as an alternative to common local antiseptics and the assumption of probiotics to maintain a eubiotic oral microbiome show promising results.

Results: Also, the FMBS percentages were significantly decreased (p < 0.0001): -15%, -20%, and -49% observed in group A, group B, and group C, respectively. The mean PPD showed significant differences (p < 0.0001): -0.10 mm, -0.40 mm, and -1.10 mm observed in group A, group B, and group C, respectively. Overall, group C showed the best improvement among the considered clinical indexes. Conclusions: The findings of this clinical trial support the use of a combined regime of the antimicrobial and anti-inflammatory effects of ozonated olive oil and the modulation of the oral microbiome of probiotic supplements as an adjunctive domiciliary strategy for patients affected by stage I and II periodontitis.