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Lactobacillus Reuteri Gums Research: Named Strains in Lozenges, a Species on the Tub
Lactobacillus reuteri gums research comes from small lozenge trials of two named strains, DSM 17938 and ATCC PTA 5289. Gum and plaque scores improved in some. ProDentim names L. reuteri by species only, with no strain code or amount, and it is a tablet, so those trials cannot be matched to it.
Written by the ProDentim label teamUpdated · 4 min read
What is Lactobacillus reuteri, and why is it linked to gums?
Lactobacillus reuteri is a lactic acid bacterium that occurs naturally in people. Researchers linked it to gums because some strains slow other bacteria that cling to teeth and gum edges in a film called plaque.
A review of the literature says L. reuteri shows promise against biofilm-linked mouth problems, but that mechanisms and benefit still need research (Liu 2025, L. reuteri oral health review). The same review asks for screening to find the best strains.
That call for strain screening is the key point for a product that names the species alone.
Gum problems start when plaque stays on the gum line and the gum becomes inflamed. Research on L. reuteri asks whether a helpful bacterium can shift that balance, and early answers are cautious.
The oral microbiome is a crowded community, and many things shape it, including diet, smoking and medical conditions (Oral microbiome review 2024 (PMC)). One bacterium among billions is a small lever.
What did the L. reuteri lozenge trials find?
Two small trials of lozenges with two named strains reported lower gum and plaque scores. Both were short, and both used lozenges.
In 45 pregnant women, lozenges with L. reuteri DSM 17938 and ATCC PTA 5289 led to lower gingival and plaque scores than placebo after birth (Schlagenhauf 2016, L. reuteri lozenges). The authors saw the lozenges as a possible add-on.
A split-mouth trial of 30 people with chronic periodontitis ran 21 days. Scores fell in all groups, most with scaling plus lozenges, so the lozenges were an add-on to professional cleaning (Vivekananda 2010, L. reuteri + SRP).
Lactobacillus paracaseiProbiotic species (strain not named)Amount: not printed- Lactobacillus reuteriProbiotic species (strain not named)Amount: not printed
B. lactis BL-04Bifidobacterium animalis subsp. lactis, strain BL-04Amount: not printed
The sales page says 3.5 billion for the three together and gives no split or strain codes except BL-04. The round bacteria pictures are brand images; none says which strain it shows (ProDentim sales page).
Why can't those results be applied to ProDentim?
They cannot, because strain, form and dose differ. Probiotic effects belong to the strain, and the ProDentim sales page names L. reuteri with no strain code (ProDentim sales page).
| Detail | Lozenge trials | ProDentim |
|---|---|---|
| Strain | DSM 17938 and ATCC PTA 5289 | Not published |
| Form | Lozenge | Soft tablet, slowly chewed |
| Amount per day | Stated in each study | Not published |
| Length | About 3 weeks and more | No trial |
A tablet that is chewed and swallowed spends less time against the gum line than a lozenge that dissolves slowly. That is a reason for caution, though no study of the tablet settles it.
What are the limits of the gum evidence?
The limits are size, length and population. The trials were small, ran for weeks and often involved people with gum inflammation already.
A larger meta-analysis found that probiotics added to dental treatment improved plaque and bleeding in periodontitis, while in gingivitis the effect was not significant overall (Benavides-Reyes 2025, probiotics & perio). The authors called for more research.
No trial reports that a probiotic replaces a dentist's cleaning. Gum disease is a dental condition that needs dental care.
What should you do for your gums in the meantime?
Brush twice a day with fluoride toothpaste, clean between your teeth daily and see a dentist if gums bleed, swell or recede.
Keep taking prescribed medicine exactly as directed, and ask a clinician first if your immune system is weak, since live probiotics can rarely cause infection (Costa 2018, probiotic infections SR). See the L. reuteri ingredient page and ProDentim side effects for the cautions.
FAQ01
L. reuteri and gum health: quick answers
Does L. reuteri heal receding gums?
No. Gum tissue that has receded does not grow back from a supplement, and none of the lozenge trials measured regrowth. They measured gum and plaque scores. See a dentist for recession.
Which L. reuteri strains were used in the gum trials?
The two trials we read used DSM 17938 and ATCC PTA 5289 in lozenges. ProDentim does not name a strain, so a match cannot be made.
Can I get L. reuteri from the ProDentim tablet at the trial dose?
That cannot be known. The tub prints no per-strain amount in the images, and the sales page gives only a total for all three strains. Without the number there is no comparison.
Is L. reuteri safe during pregnancy?
One trial used it in pregnant women, but that was a specific lozenge under study conditions. Ask your doctor or midwife before taking any supplement while pregnant or nursing.
Who wrote this02
Written and reviewed by
Pages built from the label, the sales page and linked NIH, NIDCR, FDA, CDC, ADA, FTC and peer-reviewed sources.
Last updated . Read our editorial standards and how we check reviews. This website is run by a USA authorized ProDentim retailer, not by the manufacturer. We earn money when you buy through our order links.
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