Correlation of probiotic consumption with plaque index, salivary pH, and streptococcus mutans: A clinical experimental study.

2025-11-11
The Saudi dental journal 37(10-12)

PubMed: 41214230
DOI: 10.1007/s44445-025-00010-5

Study Design

Type: Clinical Trial
Sample size: n = 40
Population: 40 research subjects aged 12-15 years at the Ibnu Hajar boarding school
Methods: A total of 40 research subjects aged 12-15 years were allocated into two groups (treatment and control), each consist of 20 subjects. Children in the treatment group took one Lactobacillus reuteri probiotic lozenge daily. Saliva samples of the subjects were taken at baseline and 7th days. Plaque index, salivary pH, and Streptococcus mutans quantification measurements were done before and after consumption of the Lactobacillus reuteri probiotic.

Background

Seventy-two percent of 12-year-old children in Indonesia experience dental caries, among 10-14-year-olds is 73%, and in 15-year-olds is 68.5%. Islamic boarding schools (pesantren) are one of the educational institutions in Indonesia, and dental caries status among the school students is moderate to severe. A preventive approach according to ecological balance has been proposed to prevent oral cavity disorders, especially dental caries.

Objectives

This study aimed to investigate the correlation of Lactobacillus reuteri probiotic consumption with plaque index, salivary pH, and Streptococcus mutans quantification.

Method

This research has been done at the Ibnu Hajar boarding school. A total of 40 research subjects aged 12-15 years were allocated into two groups (treatment and control), each consist of 20 subjects. Children in the treatment group took one Lactobacillus reuteri probiotic lozenge daily. Saliva samples of the subjects were taken at baseline and 7th days. Plaque index, salivary pH, and Streptococcus mutans quantification measurements were done before and after consumption of the Lactobacillus reuteri probiotic. Statistical analyses used the T-test and Spearman correlation test.

Results

There was a significant difference in plaque index, saliva pH, and an insignificant difference in Streptococcus mutans quantification after consuming the probiotics. The correlation coefficient between Lactobacillus reuteri probiotics consumption and plaque index is 0.672, between probiotic consumption and salivary pH is r = 0.433 (p < 0,05), while between probiotic consumption and Streptococcus mutans quantification is 0.162 (p > 0,05).

Conclusion

A significant correlation between Lactobacillus reuteri probiotic consumption with plaque index and salivary pH was found, but the correlation with Streptococcus mutans quantification was found insignificant.

Research Insights

Supplement	Dose	Health Outcome	Effect Type	Effect Size	Source
Lactobacillus reuteri ATCC PTA 5289	—	Increased Salivary pH	Beneficial	Small	View source There was a significant difference in plaque index, saliva pH, and an insignificant difference in Streptococcus mutans quantification after consuming the probiotics.
Lactobacillus reuteri ATCC PTA 5289	—	No Significant Change in Streptococcus Mutans Quantification	Neutral	Small	View source There was a significant difference in plaque index, saliva pH, and an insignificant difference in Streptococcus mutans quantification after consuming the probiotics.
Lactobacillus reuteri ATCC PTA 5289	—	Reduced Plaque Index	Beneficial	Moderate	View source There was a significant difference in plaque index, saliva pH, and an insignificant difference in Streptococcus mutans quantification after consuming the probiotics.