This study will evaluate fluoride (F) bioavailability in saliva when using an over-the-counter mouthrinse of 226 ppm F, immediately after brushing with an over-the-counter toothpaste of 1,100 ppm F or a prescription toothpaste of 5,000 ppm F. The study population will include twenty individuals, over the age of 18 years-old, from both genders, with normal oral health conditions and salivary flow rate, no need of urgent dental needs, from the Ann Arbor, MI area. Participants will be recruited from the University of Michigan School of Dentistry, in Ann Arbor, MI. Using a crossover design, twenty participants will be rotating through 4 different combinations of fluoride toothpaste (over-the-counter or prescription concentration) and fluoride mouth rinse (yes or no), in a 2 x 2 factorial design. Treatments to be tested will be as followed: Group #1 will brush with 1,100 ppm F (over-the-counter) toothpaste; Group #2 will brush with 1,100 ppm F (over-the-counter) toothpaste and rinse with over-the-counter 226 ppm F mouthrinse; Group #3 will brush with 5,000 ppm F (prescription) toothpaste; Group #4 will brush with 5,000 ppm F (prescription) toothpaste and rinse with over-the-counter 226 ppm F mouthrinse.

Inclusion Criteria:

• Sign informed consent form
• Participant understands and agrees to comply with the study protocol, and confirms availability for the entire duration of the study
• 18 years of age or older
• Good general health
• Good oral health, with no urgent treatment needs
• Normal salivary flow rate

Exclusion Criteria:

• Fail to understand or to agree to follow the study protocol
• Reduced salivary flow rate
• Poor general or oral health conditions