Experimental Dentifrice Remineralization/Fluoride Uptake in an in Situ Model

Topical fluorides have been proven to be clinically effective in the prevention of dental caries. It is generally agreed that anti-caries effect of fluoride (F) is mainly by decreasing the rate of enamel demineralization and enhancing the rate of enamel remineralization. An in-situ Surface Micro-hardness (SMH) test is widely used to evaluate enamel demineralization and remineralization during the caries process. Determination of fluoride uptake in-situ also provides better estimation of true fluoride bioavailability of fluoride dentifrice products. In this study, an in-situ remineralization fluoride uptake model will be used to compare the efficacy of experimental dentifrice with a marketed dentifrice and placebo dentifrice. Participants wore partial dentures containing two partially demineralized enamel specimens for two weeks- 24 hours per day, except when brushing (twice daily) with test dentifrice. Following each treatment period, the enamel specimens were analyzed for SMH recovery and fluoride uptake through microdrill enamel biopsy technique.

Inclusion criteria

• Age: Aged between 18 and 78
• Fluoride: Currently living in the Indianapolis area which has a fluoridated water supply (1 ppm F) and not taking fluoride supplements for medical reasons
• Dentures: Currently wearing a removable mandibular partial denture with sufficient room in the posterior buccal flange area to accommodate two enamel specimens (required dimensions 12 x 7 mm). Willing and capable of wearing their removable partial dentures 24 hours per day during the experimental periods
• Dental health:Have no current active caries or periodontal disease that may compromise the study or the health of the participants and all restorations in a good state of repair
• Salivary flow:Have a salivary flow rate in the range of normal values (unstimulated whole saliva flow rate ≥ 0.2 mL/min; gum base stimulated whole saliva flow rate ≥ 0.8 mL/min
• Compliance: Understands and is willing, able and likely to comply with all study procedures and restrictions
• Consent:Demonstrates understanding of the study and willingness to participate as evidenced by voluntary written informed consent and has received a signed and dated copy of the informed consent form
• General Health: Good general health with (in the opinion of the investigator) no clinically significant and/or relevant abnormalities of medical history or oral examination that could interfere with participant safety during the study period

Exclusion criteria

• Antibiotics:Currently taking antibiotics or have taken antibiotics in the two weeks prior to the screening visit
• Allergy/Intolerance:Known or suspected intolerance or hypersensitivity to the study materials (or closely related compounds) or any of their stated ingredients
• Pregnancy:Women who are known to be pregnant or who are intending to become pregnant over the duration of the study.
• Breast-feeding:Women who are breast-feeding.
• Clinical Study/Experimental Medication: Participation in another clinical study or receipt of an investigational drug within 30 days of the screening visit
• Personnel:An employee of the sponsor or the study site who is directly involved in the study