Impact of an Arginine-containing Toothpaste on the Subgingival Microbiota in Patients in Supportive Periodontal Care

This study aims to see how a toothpaste with arginine affects bacteria below the gum line compared to a regular fluoride toothpaste. It focuses on people with gum disease who are already getting ongoing dental care. The main questions it aims to answer are: * How does an arginine toothpaste affect the bacteria below the gumline? * How does a fluoride toothpaste affect the bacteria below the gumline? Participants will: * Use fluoride toothpaste or arginine toothpaste twice daily for 6 months * After receiving the toothpaste at the baseline visit, subjects will visit the clinic at 3 months and 6 months for additional data collection.

Inclusion Criteria: * Understands and is willing to sign an Informed Consent, approved by the local Ethics Committee. * Female or male, ages 18-95 years old (inclusive) * Systemically healthy. * Presence of at least three evaluable teeth in each quadrant. * Moderate gingival inflammation, with at least a 10% of bleeding on probing (BOP) will be required together with moderate level of plaque. * No Grade 3 Tooth Mobility * Treated stage II or III periodontitis patients, whose active treatment has finalized more than 6 months before. Stage II - Interdental clinical attachment level (CAL) at the site of greatest loss equal to 3 to 4 millimeters with maximum probing depth of less than or equal to 5 millimeters. Stage III - Interdental CAL at the site of greatest loss greater than equal to 5 millimeters, probing depth (PD) greater than or equal to 6 millimeters, and radiographic vertical bone loss * Enrolled in a periodontal maintenance treatment program * No orthodontic banding (no permanent retainers, no orthodontic appliances (i.e., no removable plastic/metal retainer) or removable prosthesis (no removable partial and/or full denture). * Subjects willing to participate and comply with the requirements of the study. * Subjects that brush their teeth regularly (once or twice daily). * Able to travel to and attend 4 research study visits over the span of the next 6 months. * Able to independently provide consent for oneself. * Fluent in reading, comprehending, and speaking English without assistance from a translator. * If a patient is using prevident, they must be willing to stop using it. Exclusion Criteria: * Untreated or uncontrolled periodontitis or advanced (advanced periodontal disease (purulent exudate, tooth mobility, and/or extensive alveolar bone loss) * Antibiotics intake within the previous month. * Pregnant women and/or breastfeeding women * Any adverse medical history (controlled and uncontrolled diabetes, osteoporosis, immunosuppression…) or long-term medication (chemotherapy and immunosuppression treatment; pharmacological treatment associated with gingival overgrowth such as the use of phenytoin, phenobarbital, lamotrigine, vigabatrin, ethosuximide, topiramate, primidone, nifedipine, amlodipine, verapamil, cyclosporine) influencing gingival conditions. * Conditions which require antibiotic prophylaxis (infectious endocarditis, cardiac valve prosthesis…). * Not willing to comply with the study protocol recommendation and visit schedule. * Current smokers or those using tobacco or vaping products. * Five (5) or more decayed, untreated dental sites (cavities) and/or any dental condition requiring urgent dental care * Currently participating in another clinical research study now and/or within the past month. * Has a history of allergies to oral care or personal care consumer products or their ingredients * Has an existing medical condition that prohibits eating or drinking for periods up to 4 hours. * Any ongoing medical condition that makes a subject unsuitable for enrollment-or any new diagnosis that arises during the study that makes the subject unsuitable to continue-may lead to exclusion, as determined by the Principal Investigator on a case by case basis. Conditions that may result in exclusion include, but are not limited to: 1. Recent myocardial infarction 2. Recent cerebrovascular accident 3. Recent placement of a cardiac valvular prosthesis 4. Severe liver dysfunction 5. Known or suspected current malignancy 6. New antibiotic use 7. Note: The Principal Investigator will review all available information about the subject and make decisions regarding both enrollment and/or continued participation.