Metagenome Resilience in Experimental Gingivitis

Study Overview
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Brief Summary
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This study aims to identify new biomarkers that indicate the resilience of individuals to developing oral disease. An 'experimental gingivitis' model will be employed in which subjects will refrain from oral hygiene in one quadrant of their mouths for 3 weeks, and will then restore oral hygiene. Gum inflammation will be monitored by clinical measures throughout the trial and samples will be collected for analysis of microbial DNA and RNA.

Detailed Description
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This project will employ an extended experimental gingivitis model to monitor changes in the oral metagenome and metatranscriptome during progression to gingivitis and recovery to oral health. The study will employ a 'split-mouth' design whereby one half of each individual's mouth is protected from oral hygiene while the other half acts as an internal control. Oral health status will be monitored through clinical measurements of dental plaque accumulation and gingival index. Plaque samples will be collected for DNA (metagenome) and RNA (metatranscriptome) sequencing. Using statistical modelling, genes and functional pathways will be identified that associate with resistance and resilience to gingivitis.

Official Title
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Functional Metagenomic Characterisation of Resilience in Experimental Gingivitis

Conditions
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Gingivitis, Oral Disease

Intervention / Treatment
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* Behavioral: Partial abstinence from oral hygiene


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: have read, understood and signed an informed consent form be adults of age 18 years or over have a minimum of 20 natural teeth (excluding third molars) be willing and able to comply with study procedures be a non-smoker and non-user of e-cigarettes or other oral intake nicotine replacement therapy (or have quit smoking/e-cigarettes/oral intake nicotine replacement therapy at least 2 years previously) healthy participants: good oral (no sites with interproximal attachment loss, GI ≥ 2.0 in ≤ 10% sites, %BOP scores ≤ 10%) and good general health. Covid-19 negative by LFT and fully vaccinated Exclusion Criteria: infectious or systemic diseases that may be unduly affected by participation in this study extensive crown or bridge work and/or rampant decay at the discretion of the examiner wear removable partial dentures, a fixed/removable orthodontic appliance diabetes history of xerostomia, salivary gland disease, head and neck radiotherapy, Sjögren's syndrome, mucocutaneous disorders of the oral cavity, vesicobullous disorders of the oral cavity smoking or use of e-cigarettes within the last 2 years current use of prescription or over-the-counter medications that could affect salivary flow, at the discretion of the examiner lack of capacity to be able to consent to the research project and/or inability to follow study instructions pregnant by medical history or nursing currently undergoing or requiring extensive dental, orthodontic or implant treatment, or treatment for peri-implantitis treatment with antibiotics for any medical or dental condition within 4 weeks prior to enrolment scale and polish within 4 weeks prior to enrolment long term use of antibiotics or non-steroidal anti-inflammatory drugs (prophylactic low dose aspirin is permitted though) evidence of drug induced gingival overgrowth participation in a dental research study within the previous 20 days. Unilever personnel and personnel in the University department performing the study

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental gingivitis<br>Group will wear a splint during oral hygiene to cover one quadrant of their dentition. They will develop gingivitis over 3 weeks. They will practise normal oral hygiene in the rest of their mouth (with minor restrictions, e.g. no mouthwash) and one other quadrant will act as an internal control for the gingivitis. After 3 weeks, normal oral hygiene will be restored throughout the mouth and subjects will continue to be monitored for a further 3 weeks. | Behavioral: Partial abstinence from oral hygiene<br>* One quadrant of the dentition will be protected from oral hygiene for 3 weeks.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Metagenomic sequence | Change from baseline | Intervals up to 6 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Metatranscriptomic sequence | Change from baseline | Intervals up to 6 weeks | 
| Lobene Modified Gingival Index: Min 0 - Max 4; Worse- higher score indicates more gingival inflammation | Change from baseline | Intervals up to 6 weeks | 
| Plaque Index (Modified Quigley & Hein): Min 0 - Max 5; Worse - higher score indicates more plaque | Change from baseline | Intervals up to 6 weeks | 
| Bleeding Index (Bleeding on probing): Min 0 - Max 1; Worse- higher score indicates a bleeding site | Change from baseline | Intervals up to 6 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Experimental gingivitis, Dental plaque, Metagenome, Oral health