A Study to Investigate the Antimicrobial Activity of 2 Test Toothpastes

Inclusion Criteria: * Demonstrates understanding of the study procedures, restrictions and willingness to participate as evidenced by voluntary written informed consent and has received a signed and dated copy of the informed consent form. * Good general and mental health with, in the opinion of the investigator or medically qualified designee no clinically significant and relevant abnormalities in medical history or upon oral examination. * Plaque sample acidogenicity in the pH range 5.0 to 5.7 at Visit. Exclusion Criteria: * Women who are known to be pregnant or who are intending to become pregnant over the duration of the study. * Women who are breast-feeding. * Currently taking antibiotics or have taken antibiotics within 2 weeks of plaque assessment (Visit 2). A participant with any medical history that may prevent them from participating in the study until study conclusion (such as diabetes). * Any sign of grossly carious lesions (active), moderate or severe periodontal conditions, or severe tooth wear. * Known or suspected intolerance or hypersensitivity to the study materials (or closely related compounds) or any of their stated ingredients. * Current smokers, or smokers who have quit within 6 months of screening, or participants currently using smokeless forms of tobacco, e.g. Gutkha, Pan containing tobacco, Pan Masala. * Current active caries or periodontitis that may compromise, in the opinion of the investigator, study outcomes or the health of the subject. * Restorations in a poor state of repair that may, in the opinion of the investigator, compromise study outcomes or the health of the participant. * Partial dentures or orthodontic appliances that may, in the opinion of the investigator, compromise study outcomes or the health of the participant. * Recent history (within the last year) of alcohol or other substance abuse.