Intra Oral Kinetics of Fluoride Containing Dentifrices

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 * Aged 18-65 years * Understands and is willing, able and likely to comply with all study procedures and restrictions * Good general and mental health with, in the opinion of the investigator or medically qualified designee: 1. No clinically significant and relevant abnormalities of medical history or oral examination 2. Absence of any condition that would impact on the participant's safety or well being or affect the individual's ability to understand and follow study procedures and requirements * A minimum of 20 permanent natural teeth * A gum-base stimulated whole saliva flow rate ≥ 0.8 mL/min and an unstimulated whole saliva flow rate ≥ 0.5 mL/min. Exclusion Criteria: * Pregnant or breast feeding women * Presence of chronic debilitating disease. * Any condition that causes xerostomia as determined by the Investigator. * Evidence of untreated caries. * Gross periodontal disease. * Tongue or lip piercing or presence of dental implants. Professional tooth cleaning or dental treatment during study. Oral surgery or extraction within 6 weeks of the screening visit. * Self reported oral symptoms including lesions, sores or inflammation * Known or suspected intolerance or hypersensitivity to the study materials (or closely related compounds) or any of their stated ingredients * Currently taking antibiotics or have taken antibiotics within 2 weeks of the screening visit * Any medication that could affect salivary flow or cause xerostomia as determined by the Investigator * Use of multivitamins, calcium supplements and or fluoride supplements within 7 days of treatment phase * Participant unwilling to abstain from smoking for at least 4 hours on the day of each test visit * Recent history (within the last year) of alcohol or other substance abuse.