Effect of drops containing Lactobacillus reuteri (DSM 17938 and ATCC PTA 5289) on plaque acidogenicity and other caries-related variables in orthodontic patients

Abstract

Background The purpose of the study was to investigate the effect of probiotics on biofilm acidogenicity and on the number of salivary Streptococcus mutans and lactobacilli in orthodontic patients. Methods This RCT was conducted on 28 young adults who were undergoing orthodontic treatment. The short-term prospective clinical trial lasted for three weeks. The test group rinsed daily with drops containing two Lactobacillus reuteri strains diluted in water, while the placebo group used drops without probiotics. The subjects were enrolled eight months since the beginning of orthodontic treatment. Plaque-pH, saliva and dental biofilm samples were obtained at baseline, one week and three weeks post intervention. Results Twenty-seven subjects successfully completed the trial period, only one drop out in the test group. No side effects were reported. A statistically significant increase in plaque pH at three weeks post-intervention was found for the test group (p < 0.05), while insignificant changes in the pH value were found for the placebo group in comparison to baseline (p > 0.05). In addition, the AUC7.0 showed a significant difference at three weeks between the test and placebo (p = 0.00002). The three-week samples of stimulated whole saliva showed a statistically insignificant difference in the number of S. mutans and lactobacilli between the two groups (p > 0.05). The qPCR analysis showed the ability of the two strains to get colonized in the dental biofilm without a significant effect on the microbial counts. Conclusion/clinical implications A mixture of Lactobacillus reuteri has the ability to reduce the pH fall at the three-week follow-up. However, the short-term use of probiotics does not appear to have an effect on the number of salivary Streptococcus mutans and lactobacilli in saliva and on the dental biofilm. Trial registration Clinicaltrial.gov (Identifier: NCT04593017/ (19/10/2020)).

Effects of probiotics on the oral health of patients undergoing orthodontic treatment: a systematic review and meta-analysis

“…2 . Six studies were considered as ‘low RoB’ [ 20 , 26 , 27 , 32 , 33 , 36 ] for all the key domains. Six studies were considered to have ‘some concerns’ [ 22 , 25 , 30 , 31 , 34 , 35 ], whereas three studies [ 19 , 21 , 29 ] were considered to have a ‘high RoB’.…”

“…Regarding probiotic delivery vehicles, four studies used mouthwash [ 19 , 21 , 25 , 27 ], six studies used lozenges [ 20 , 26 , 29–32 ], three studies used yoghurt [ 22 , 33 , 36 ], and two studies used toothpaste [ 34 , 35 ]. In terms of probiotic species, most studies used a mix of probiotic species, whereas five studies used a single probiotic species [ 20 , 21 , 25 , 33 , 36 ].…”

“…[ 21 ] observed a significant decrease in S. mutans counts from 7.1 × 10 4 CFU/ml to 1.1 × 10 3 CFU/ml after 28 days of using probiotic mouthwash. Of the six studies [ 27 , 30 , 32–34 , 36 ] that evaluated Lactobacillus counts in the saliva or plaque of patients, Alp and Baka [ 34 ] and Gizani et al . ( 32 ) found significant reductions in Lactobacillus counts ( P < .05).…”

Strategies to Combat Caries by Maintaining the Integrity of Biofilm and Homeostasis during the Rapid Phase of Supragingival Plaque Formation

“…In caries prevention, probiotics can colonize the oral cavity and displace cariogenic bacteria. In general, probiotics can produce various antimicrobial substances—such as bacteriocins and bacteriocin-like peptides, lactic acid, and H 2 O 2 —that increase the medium’s pH and activate immune response cells such as macrophages, neutrophils, and natural killer cells to attack pathogens [ 107 , 108 , 109 , 110 , 111 , 112 ].…”

“…Various species of the genus Lactobacillus —including Lactobacillus reuteri , Lactobacillus brevis , Lactobacillus rhamnosus GG, Lacticaseibacillus casei , Lactobacillus plantarum , and L. lactis —have been reported to produce inhibitory substances such as ammonia that buffer the pH in saliva to prevent the growth of S. mutans [ 107 , 109 , 117 ]. Furthermore, as already mentioned, L. lactis produces nisin, a natural antimicrobial peptide highly active against Gram-positive bacteria with a potential role as a caries-preventive agent in the oral cavity with an effect on cariogenic bacteria and root canal pathogens.…”