Thirty-six teenagers in Bantul sat in examination chairs with their mouths open as their plaque and calculus indices were measured one by one. For the next two months, some of them would suck on small lozenges containing live bacteria twice a day. Not mouthwash, not a special toothpaste—just a probiotic lozenge. The question was whether these beneficial bacteria would be enough to change the fate of their teeth.
This was the starting point of research conducted by Prof. Dr. drg. Regina TC. Tandelilin, M.Sc., PBO, together with a team from the Faculty of Dentistry, Universitas Gadjah Mada, Yogyakarta, in collaboration with researchers from the University of Bari Aldo Moro, Italy. The findings were published in the May–June 2018 issue of the Journal of International Oral Health.
The Mouth Is More Than Just an Entryway
The oral cavity is not an empty space. Millions of microorganisms live inside it; some are beneficial, while others cause disease. When this microbial ecosystem becomes unbalanced, problems can arise: caries, gingivitis, halitosis, and even candidiasis.
Dental caries remains one of the most common chronic diseases worldwide, including in Indonesia. The process begins with interactions among pathogenic bacteria, food residues, and host conditions that allow organic acids to form. These acids gradually erode enamel and dentin. Conventional approaches such as fluoride and regular toothbrushing have already been proven effective, but researchers continue to seek additional strategies, particularly for high-risk groups.
Oral probiotics have emerged as an interesting candidate. Bacteria such as Streptococcus salivarius M18 are known to produce bacteriocins that can kill Streptococcus mutans, a key bacterium in the formation of cariogenic plaque. In addition, the dextranase and urease enzymes produced by these bacteria can inhibit plaque formation while increasing salivary pH.
Bantul High School Students Become Research Participants
The research team randomly selected a private high school in Bantul Regency. Of the 96 students aged 15–19 years who met the eligibility criteria, 36 individuals classified as being at high risk of caries based on the CAMBRA (Caries Management by Risk Assessment) methodology were selected to participate in the 60-day clinical trial.
They were divided into two groups: 18 participants in the treatment group consumed two probiotic lozenges (Hyperbiotics Pro-Dental, USA) each day after brushing their teeth, while 18 participants in the control group continued to brush their teeth as usual. The study was designed as a randomized, double-blind trial. Measurements were taken on days 0, 30, and 60, covering the plaque index, debris index, calculus index, OHI-S, salivary pH, buffer capacity, and salivary flow rate.
The research protocol received approval from the FKG UGM Ethics Committee under number 001264/KKEP/FKG-UGM/EC/2017, and all participants’ parents signed informed consent forms.
What Changed After Two Months
The results were not dramatic, but they were statistically meaningful.
In the treatment group, the plaque index decreased significantly from day 0 to day 60 (p = 0.003). The calculus index also showed a significant decrease between days 0 and 30 (p = 0.011). Mean salivary pH also tended to increase from 6.4 to 6.7, approaching a neutral level that is more protective against tooth demineralization.
“These results indicate that routine use of oral probiotics can reduce plaque accumulation and calculus formation in treated participants, and their application may be proposed as an effective agent for inhibiting dental plaque and calculus accumulation in populations at high risk of caries.”
However, there is an important qualification: when the treatment and control groups were directly compared on days 30 and 60, the differences did not reach statistical significance. This means that the probiotic effect was clearly observed over time within the treatment group, but was not yet strong enough to clearly distinguish the two groups, possibly because of the relatively small sample size and short observation period.
The research team openly acknowledged these limitations: there was no positive control group, the number of participants was limited, and the 60-day observation period was still relatively short for assessing the overall impact on dental caries.
One Small Lozenge, One Big Question
Amid growing global antibiotic resistance, a probiotic-based approach offers something different: a natural therapy that works by strengthening the microbial ecosystem rather than destroying it. Probiotics do not kill all bacteria; instead, they compete with, displace, and modify the environment to make it less hospitable to pathogens.
This study opens opportunities for further research involving larger populations, longer durations, and stronger positive control groups. If the findings remain consistent, probiotic lozenges could become part of caries-prevention protocols, particularly for high-risk groups requiring additional protective strategies beyond toothbrushing and fluoride.
The remaining question is no longer whether beneficial bacteria can help. The question now is: how far can we rely on them?
Source DOI: DOI: 10.4103/jioh.jioh_82_18
Authors: Anny Anggraini; drg. Achmad Zam Zam Aghasy, M.Kes.
Photo: Pexels