An interventional study of Probiotic Blend Lozenge and Placebo Lozenge in Periodontal Disease, sponsored by University of New Hampshire. Not yet recruiting. Open to participants aged 45 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-07-21.
Sponsored by University of New Hampshire · Not applicable, Interventional, and Treatment
Probiotics are live microorganisms that can be taken as supplements and have shown promise in playing a beneficial role in improving clinical conditions that are characterized by chronic inflammation, such as periodontal disease (PD). The human gut microbiome is composed of trillions of bacteria that reside throughout the gastrointestinal tract and has an important role in the modulation of inflammatory responses in the human host. There is evidence that PD is associated with alterations in the oral and gut microbiomes, suggesting that probiotics may reduce inflammation through microbiome modulation. However, individual responses to probiotics can be highly variable, and robust predictors of probiotic responsiveness remain poorly defined. There is also limited knowledge about how the oral and gut microbiome interact even though there is growing evidence for a bidirectional oral-gut axis with implications for host immunity, inflammation, and probiotic responsiveness. The overarching goal of this project is to identify oral and gut microbiome features that predict responsiveness to probiotic interventions as an adjuvant treatment for PD. We will conduct a double-blind randomized controlled trial in which New Hampshire adults with stage III PD will be randomized to receive a 12-week adjuvant intervention of either a daily probiotic (n=45) or placebo (n=45) lozenge. The probiotic intervention will consist of a once daily lozenge containing a standard dose of 200 million CFU of two strains of Limosilactobacillus reuteri (DSM 17938 and ATCC PTA 5289), a commercial formulation demonstrated to be safe and well-tolerated in this population over this treatment length. The primary outcome to quantify responsiveness to the probiotic as an adjuvant therapeutic for PD will be within-subject change from baseline in inflammatory markers, and oral and gut microbiome composition.
867 studies on the registry are indexed under Periodontal Diseases; 189 are open to participants now.
This study's planned enrollment of 100 is above the median of 45 across 557 interventional studies indexed under Periodontal Diseases.
Browse Periodontal Diseases studies →University of New Hampshire is the lead sponsor of 15 studies on the registry; 4 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Placebo lozenge (Ingredients: Isomalt, xylitol, peppermint flavor, menthol flavor and calcium sterate)
Dietary Supplement: Placebo Lozenge
Probiotic lozenge (Ingredients: Limosilactobacillus reuteri, isomalt, xylitol, peppermint flavor, menthol flavor and calcium sterate)
Dietary Supplement: Probiotic Blend Lozenge
L. reuteri is a probiotic that has been shown to inhibit the activity of "red complex" species and reduce PD severity in vitro and in animal models, and has been shown to ameliorate clinical outcomes of PD in human trials.
Daily placebo lozenge.
Matrix metalloproteinase-8 (MMP-8)in gingival crevicular fluid (GCF)
MMP-8 is a validated biomarker of periodontal collagen breakdown
Time frame: Change from baseline to week 12
C-reactive protein (CRP) in saliva and plasma
CRP is an acute phase protein used as marker of oral and systemic inflammation
Time frame: Change from baseline to week 12
Interleukin 1β (IL-1β) in saliva and plasma
Interleukin IL-1β is a pro-inflammatory cytokine measured in saliva and plasma as an indicator of systemic and oral inflammatory response.
Time frame: Change from baseline to week 12
IL-6 in saliva and plasma
Il-6 is a pro-inflammatory cytokine measured in saliva and plasma as an indicator of systemic and oral inflammatory response.
Time frame: Change from baseline to week 12
IL-8 in saliva and plasma
IL-8 is a chemokine involved in neutrophil recruitment and local inflammatory activity, measured as a marker of periodontal inflammatory response.
Time frame: Change from baseline to week 12
Tumor necrosis factor-alpha (TNF-α) in saliva and plasma
TNF-α is a pro-inflammatory cytokine associated with tissue inflammation and periodontal disease activity, measured to assess inflammatory modulation following probiotic supplementation.
Time frame: Change from baseline to week 12
Oral microbiome composition
Relative abundance and diversity of bacterial taxa in oral samples, assessed to determine whether probiotic supplementation alters the microbial community associated with periodontal disease.
Time frame: Change from baseline to week 12
Gut microbiome composition
Relative abundance and diversity of bacterial taxa in stool samples, assessed to evaluate whether probiotic supplementation affects gut microbial ecology.
Time frame: Change from baseline to week 12
Oral and gut microbiome functional potential
Predicted or measured microbial gene pathway profiles, assessed to identify functional microbial features associated with inflammatory response and probiotic responsiveness.
Time frame: Change from baseline to week 12
No study locations are listed for this record.
Plan to share: No — All results will be reported in aggregate form using summary statistics. No direct identifiers will be included in publications, presentations, or shared datasets. Analytic files will contain only coded data linked to unique study IDs. Because the study will enroll participants within a defined age range and geographic region, demographic variables will be reported in grouped categories, and small cell sizes will be aggregated or not report to prevent potential re-identification.
No publications or documents are linked to this record.
Start is estimated for Oct 2026; primary completion for Nov 2027, 13 months later.
Of 312 non-industry interventional studies with no phase under Periodontal Diseases, half reached primary completion within 13 months of starting (the median), counting those still running; a quarter within 8 and three quarters within 27. This study's planned 13 months is close to that.
Counting every sponsor, half of 331 studies reached it within 13 months; a quarter within 8 and three quarters within 26.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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University of New Hampshire