Dysbiosis of Methanogenic Archaea and Nanoarchaea in the Oral Microbiome

Study Design A cross-sectional case-control study. Participation in the study will be offered to all eligible subjects who meet the inclusion criteria.

Number of Patients 250 patients. For each patient, a dental plaque sample and a saliva sample will be collected during the visit.

Inclusion criteria

Case selection criteria:

Cases are defined as subjects with oral health vulnerability

• Men or women aged 60 years or older
• and/or immunocompromised individuals without periodontal disease (gingivitis, periodontitis, and peri-implantitis) clinically diagnosed by the dentist during the consultation.
• Patients who have received information about the study and have not expressed objection
• Patients who are beneficiaries or eligible for a social security program Control group selection criteria Controls are defined as subjects without oral health vulnerability • Men and women under 60 years of age without periodontal disease (gingivitis, periodontitis, and peri-implantitis) clinically diagnosed by the dentist during the consultation.

The clinical examination allows for the diagnosis of the absence or presence of periodontal disease, with particular attention to: bleeding on probing, the depth of periodontal pocket(s), tooth mobility, bone destruction in furcation areas, and the assessment of radiographic bone level taking age into account.

Exclusion criteria

• Patients who are currently excluded from another research protocol at the time the informed consent form is collected.
• Subjects covered by Articles L1121-5 through L1121-8 of the Public Health Code (minors, adults under guardianship or conservatorship, patients deprived of their liberty, pregnant or breastfeeding women),
• Men and women with periodontal disease (gingivitis, periodontitis, and peri-implantitis)
• Men and women with any systemic disease
• Men and women currently undergoing drug treatment