Effect of Dentifrice Usage Regime on Delivery and Efficacy of Fluoride

Phase 4

Completed

Conditions: Dental Caries

Interventions: Drug: Sodium fluoride / silica and carbopol, 0.5g
Drug: Sodium fluoride / silica and carbopol, 1.5g
Other: Fluoride free dentifrice

Registration Number: NCT01563172

Lead Sponsor: GlaxoSmithKline

Brief Summary: This study will evaluate and compare the effect of the amount of toothpaste used and brushing time on enamel strengthening (percent of surface microhardness recovery, % SMHR) and enamel fluoride uptake (EFU).

Detailed Description: Not available

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 65

Inclusion Criteria

General and Dental Health

Good general and dental health with (in the opinion of the investigator) no clinically significant and relevant abnormalities of medical history or oral examination
Have no current active caries or periodontal disease that may compromise the study or the health of the subjects
Residency: Currently living in the Indianapolis, Indiana area

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 mm x 7 mm)
Willing to have their denture modified to accommodate enamel test specimens and willing and capable of wearing their removable mandibular partial dentures 24 hours per day during the experimental periods
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/minute; gum base stimulated whole saliva flow rate ≥ 0.8 mL/minute)

Exclusion Criteria

Antibiotics: Use of antibiotics two weeks prior to a treatment visit or anticipated use during the study treatment periods
Study Scale Use: Subjects unable to measure product weights accurately using the assigned study scale as determined by the study staff (as demonstrated on or before Visit 4)
A member of the site study staff who is directly working on the project or living in that staff's household
Any employee of any toothpaste manufacturer or their spouse or family member

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Experimental dentifrice 0.5g, 45 seconds brushing group	Sodium fluoride / silica and carbopol, 0.5g	Participants brush twice a daily for 45 seconds with experimental dentifrice.
Experimental dentifrice 0.5g, 45 seconds brushing group	Fluoride free dentifrice	Participants brush twice a daily for 45 seconds with experimental dentifrice.
Experimental dentifrice 1.5g, 45 seconds brushing group	Sodium fluoride / silica and carbopol, 1.5g	Participants brush twice a daily for 45 seconds with experimental dentifrice.
Experimental dentifrice 1.5g, 45 seconds brushing group	Fluoride free dentifrice	Participants brush twice a daily for 45 seconds with experimental dentifrice.
Experimental dentifrice 0.5g, 2 minutes brushing group	Sodium fluoride / silica and carbopol, 0.5g	Participants brush twice a daily for 2 minutes with experimental dentifrice.
Experimental dentifrice 0.5g, 2 minutes brushing group	Fluoride free dentifrice	Participants brush twice a daily for 2 minutes with experimental dentifrice.
Experimental dentifrice 1.5g, 2 minutes brushing group	Sodium fluoride / silica and carbopol, 1.5g	Participants brush twice a daily for 2 minutes with experimental dentifrice.
Experimental dentifrice 1.5g, 2 minutes brushing group	Fluoride free dentifrice	Participants brush twice a daily for 2 minutes with experimental dentifrice.
Contol group	Sodium fluoride / silica and carbopol, 1.5g	Participants brush twice a daily for 2 minutes with controll dentifrice.
Contol group	Fluoride free dentifrice	Participants brush twice a daily for 2 minutes with controll dentifrice.

Primary Outcome Measures

Name	Time	Method
Percentage Surface Micro Hardness Recovery (% SMH), of Brushing for 2 Minutes Versus (vs.) Brushing for 45 Seconds With 1.5g of Experimental Dentifrice.	At Baseline and at Day 14	SMH recovery test was used to assess the changes in mineralization status of enamel specimens using a Wilson 2100 Hardness tester. SMH recovery was performed in-vitro and determined by measuring the length of the indentations of enamel specimens. An increase in the indentation length compared to the baseline indicates softening while decrease in the indentation length represents re-hardening of enamel surface. % SMH recovery was calculated from indentation length (micrometer \[μm\]) of sound enamel specimen at baseline (B), indentation length (μm) after in vitro demineralization (D1), indentation length (μm) after intra-oral exposure (R): \[D1-R/D1-B\] ×100.

Secondary Outcome Measures

Name	Time	Method
Percentage Surface Micro Hardness (% SMH) Recovery, of Brushing for 2 Minutes With 0.5g of Experimental Dentifrice vs. Brushing for 2 Minutes With 1.5g of Experimental Dentifrice.	At Baseline and at Day 14	SMH recovery test was used to assess the changes in mineralization status of enamel specimens using a Wilson 2100 Hardness tester. SMH recovery was performed in-vitro and determined by measuring the length of the indentations of enamel specimens. An increase in the indentation length compared to the baseline indicates softening while decrease in the indentation length represents re-hardening of enamel surface. % SMH recovery was calculated from indentation length (μm) of sound enamel specimen at baseline (B), indentation length (μm) after in vitro demineralization (D1), indentation length (μm) after intra-oral exposure (R): \[D1-R/D1-B\] ×100.
Percentage Surface Micro-hardness Recovery (% SMH), of Brushing for 45 Seconds With 0.5g of Experimental Dentifrice vs. Brushing for 45 Seconds With 1.5g of Experimental Dentifrice.	At Baseline and at Day 14	SMH recovery test was used to assess the changes in mineralization status of enamel specimens using a Wilson 2100 Hardness tester. SMH recovery was performed in-vitro and determined by measuring the length of the indentations of enamel specimens. An increase in the indentation length compared to the baseline indicates softening while decrease in the indentation length represents re-hardening of enamel surface. % SMH recovery was calculated from indentation length (μm) of sound enamel specimen at baseline (B), indentation length (μm) after in vitro demineralization (D1), indentation length (μm) after intra-oral exposure (R): \[D1-R/D1-B\] ×100.
Percentage Surface Micro Hardness (% SMH) Recovery , of Brushing for 2 Minutes vs. Brushing for 45 Seconds With 0.5g of Experimental Dentifrice.	At Baseline and at Day 14	SMH recovery test was used to assess the changes in mineralization status of enamel specimens using a Wilson 2100 Hardness tester. SMH recovery was performed in-vitro and determined by measuring the length of the indentations of enamel specimens. An increase in the indentation length compared to the baseline indicates softening while decrease in the indentation length represents re-hardening of enamel surface. % SMH recovery was calculated from indentation length (μm) of sound enamel specimen at baseline (B), indentation length (μm) after in vitro demineralization (D1), indentation length (μm) after intra-oral exposure (R): \[D1-R/D1-B\] ×100.
Percent Surface Micro-hardness (% SMH) Recovery, of Brushing for 2 Minutes With 1.5g of Experimental Dentifrice vs. Brushing for 2 Minutes With 1.5g of an Control Dentifrice.	At Baseline and at Day 14	SMH recovery test was used to assess the changes in mineralization status of enamel specimens using a Wilson 2100 Hardness tester. SMH recovery was performed in-vitro and determined by measuring the length of the indentations of enamel specimens. An increase in the indentation length compared to the baseline indicates softening while decrease in the indentation length represents re-hardening of enamel surface. % SMH recovery was calculated from indentation length (μm) of sound enamel specimen at baseline (B), indentation length (μm) after in vitro demineralization (D1), indentation length (μm) after intra-oral exposure (R): \[D1-R/D1-B\] ×100.
Enamel Fluoride Uptake (EFU) After Brushing for 2 Minutes vs. Brushing for 45 Seconds With 1.5g of Experimental Dentifrice.	At Day 14	EFU was measured by using micro-drill analysis of the enamel specimens carried out after 14 days of intra-oral exposure for each of the toothpaste treatments. The amount of fluoride-uptake by enamel was calculated based on the amount of fluoride divided by the area of the enamel cores.
Enamel Fluoride Uptake (EFU) After Brushing for 2 Minutes vs. Brushing for 45 Seconds With 0.5g of Experimental Dentifrice.	At Day 14	EFU was measured by using micro-drill analysis of the enamel specimens carried out after 14 days of intra-oral exposure for each of the toothpaste treatments. The amount of fluoride-uptake by enamel was calculated based on the amount of fluoride divided by the area of the enamel cores.
Enamel Fluoride Uptake (EFU) After Brushing for 2 Minutes With 0.5g of Experimental Dentifrice vs. Brushing for 2 Minutes With 1.5g of Experimental Dentifrice.	At Day 14	EFU was measured by using micro-drill analysis of the enamel specimens carried out after 14 days of intra-oral exposure for each of the toothpaste treatments. The amount of fluoride-uptake by enamel was calculated based on the amount of fluoride divided by the area of the enamel cores.
Enamel Fluoride Uptake (EFU) After Brushing for 45 Seconds With 0.5g of Experimental Dentifrice vs. Brushing for 45 Seconds With 1.5g of Experimental Dentifrice.	At Day 14	EFU was measured by using micro-drill analysis of the enamel specimens carried out after 14 days of intra-oral exposure for each of the toothpaste treatments. The amount of fluoride-uptake by enamel was calculated based on the amount of fluoride divided by the area of the enamel cores.
Enamel Fluoride Uptake (EFU) After Brushing for 2 Minutes With 1.5g of Experimental Dentifrice vs. Brushing for 2 Minutes With 1.5g of Control Dentifrice.	At Day 14	EFU was measured by using micro-drill analysis of the enamel specimens carried out after 14 days of intra-oral exposure for each of the toothpaste treatments. The amount of fluoride-uptake by enamel was calculated based on the amount of fluoride divided by the area of the enamel cores.