Effects of Mouthwashes on the Oral Microbiome and Systemic Health

NCT07356271 · Status: NOT_YET_RECRUITING · Phase: EARLY_PHASE1 · Type: INTERVENTIONAL · Enrollment: 200

Last updated 2026-02-17

No results posted yet for this study

Summary

OVERVIEW

While antimicrobial mouthwashes are proven to be clinically effective for management of certain oral microbial diseases, recent studies suggest tha, in addition to targeting bacteria responsible for gum diseases such as gingivitis and periodontitis, they may harm healthy bacteria and disturb the balance and protective role of the oral microbiome (dysbiosis).

Most findings on the oral microbiome and mouthwashes involve chlorhexidine use, demonstrating that it may induce dysbiosis and compromise the host oral microenvironment . A recent study completed in 2025 has shown that CPC mouthwash can also inhibit nitrate synthesis in the mouth. However there remains a need for further research on other agents used in mouthrinses, such as hydrogen peroxide, essential oils, to determine whether their clinical effectiveness in managing oral disease is accompanied by changes to the oral microbiome. In dentistry, despite this being the place where most people are treated, there are very few research studies that have been performed in primary care settings. Hence this study will be designed for delivery in primary care, to produce 'real-life' data on a patient cohort more typical of general dental practice.

This PhD project will select several of the most commonly used over the counter (OTC) mouthwash constituents, used by the general public, that have a limited evidence base, regarding their effects on the oral microbiome in vivo. . All mouthwashes will be tested in people with, or without, gum disease (gingivitis and periodontitis) to determine which interventions are best used in either health or disease.

Conditions

Interventions

DRUG

Use of mouthwashes

Population This study aims to recruit up to 200 participants over a period of 3 years on a part-time basis. Recruitment will be carried out through three sites: (i) the University of Plymouth campus population (as successfully used in earlier studies such as Bescos et al., 2020), (ii) the Peninsula Dental School / Peninsula Dental Social Enterprise (PDSE) triage patient clinics (non-NHS clinics), and (iii) the Southside Dental Practice, a private primary care practice located in Southsea, Portsmouth. Sample size was calculated using G\*Power software, which showed that usually 20-30 participants per group are enough, depending on whether the focus is clinical outcomes, blood markers, or microbiome changes. For this project, the main outcome is clinical effectiveness, measured through changes in plaque and bleeding scores. The PDSE clinics collectively see around 400 patients per day across their sites, providing a large and diverse pool of potential participants. In compariso

Sponsors & Collaborators

  • University of Plymouth

    lead OTHER

Principal Investigators

  • zoe Brookes, PhD · University of Plymouth

Study Design

Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
TRIPLE
Model
PARALLEL

Eligibility

Min Age
18 Years
Sex
ALL
Healthy Volunteers
Yes

Timeline & Regulatory

Start
2026-02-01
Primary Completion
2028-02-01
Completion
2029-03-01

More Related Trials

Entities

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT07356271 on ClinicalTrials.gov