Protection From Dental Erosion: All Fluorides are Not Equal.

All fluoride sources help strengthen teeth against bacterial acids that cause caries. However, excessive exposure to dietary acids, which can result in dental erosion, presents a more aggressive level of challenge compared to caries. Despite the fact that almost all toothpastes contain fluoride, both the incidence and prevalence of dental erosion appear to be on the rise.

Protective benefits of a stabilised stannous-containing fluoride dentifrice against erosive acid damage.

Purpose: To assess the potential of a stabilised stannous (Sn)-containing NaF dentifrice (Oral B/blend-a-Med(®) Pro-Expert), in addition to a number of other marketed European dentifrices formulated with various fluoride actives and two control dentifrices, to protect enamel against erosive acid damage.

Methods: Cores of human enamel (four per group) were soaked in pooled human saliva, and then treated with a 1:3 slurry (dentifrice:saliva) using a standardised in vitro erosion model (5-day cycling) that includes 10-minute challenges with 1% citric acid applied 60 minutes after each dentifrice treatment. Enamel surface loss was measured using transverse microradiography (TMR).

Erosion protection comparison of stabilised SnF2 , mixed fluoride active and SMFP/arginine-containing dentifrices.

Purpose: To investigate the relative erosion protection potential of marketed dentifrices formulated with either stabilised stannous fluoride (SnF2 ), sodium fluoride (NaF) and/or sodium monofluorophosphate (SMFP) using an established laboratory erosion cycling model.

Methods: Sound enamel cores from extracted, human enamel were cleaned, ground and polished, soaked in pooled saliva (pellicle formation) and treated with a 1:3 slurry of dentifrice and saliva. Specimens were subjected to daily challenges with 1% citric acid, a potentially damaging acid found in common food and drinks.

Protective effects of SnF2 - Part III. Mechanism of barrier layer attachment.

Objective: To assess the ability of various fluoride salts to protect enamel against acid attack via a barrier mechanism.

Methods: Extracted human enamel specimens were cleaned and rinsed, then soaked in pooled human saliva for 1 hour to initiate formation of an early pellicle. Groups of three specimens each were etched for 10 minutes in 1% citric acid (pH 2.

Protective effects of SnF2 - Part II. Deposition and retention on pellicle-coated enamel.

Unlabelled: Deposition of an acid-resistant barrier onto enamel represents a potentially superior means for delivering protection against dietary, erosive acid challenges.

Purpose: The purpose of this study was to demonstrate the ability of a stabilised stannous fluoride (SnF2 ) dentifrice to: (1) deposit a SnF2 barrier layer onto pellicle-coated enamel surfaces; (2) increase the intensity of the barrier layer over time; and (3) be retained on the enamel surface for hours after product use.

Methods: Squares of human enamel were exposed to pooled saliva for 1 hour (pellicle formation) and separated into six sets.

Protective effects of SnF2 - Part I. Mineral solubilisation studies on powdered apatite.

Purpose: To compare the ability of two active ingredients - sodium fluoride (NaF) and stannous fluoride (SnF2 ) - to inhibit hydroxyapatite (HAP) dissolution in buffered acidic media.

Methods: Two in vitro studies were conducted. HAP powder, which is representative of tooth mineral, was pretreated with: test solutions of NaF or SnF2 , 10 g solution per 300 mg HAP powder (Study 1); or NaF or SnF2 dentifrice slurry supernatants, 20 g supernate per 200 mg HAP powder for 1 minute followed by three washes with water, then dried (Study 2).

The Featherstone laboratory pH cycling model: a prospective, multi-site validation exercise.

Purpose: To demonstrate the robustness of the Featherstone pH cycling model when tested in three independent laboratories and to evaluate the use of "non-inferiority" testing at those laboratories.

Methods: The fundamental principles for the Featherstone laboratory pH cycling model to be an appropriate alternative to animal testing is that it must demonstrate equivalent accuracy to the "Gold Standard" (rat caries model) by: (1) providing a meaningful representation of the caries process; (2) demonstrating a proportionate response to fluoride dose (or concentration); (3) being able to show that clinically proven formulations perform similarly relative to the controls; and (4) differentiating products that have attenuated fluoride activity.

Results: This cross-validation study confirmed the ability of the three independent laboratories to discriminate between various concentrations of fluoride-containing dentifrice formulations, demonstrated that clinically proven formulas perform as expected and identified an attenuated fluoride formulation (NaF/CaCO3 dentifrice - 1100 ppm NaF) as inferior compared to the 1100 ppm F (NaF/silica) positive control.

Recommendation for a non-animal alternative to rat caries testing.

Purpose: As a requirement of the Food & Drug Administration's final monograph on "Anticaries drug products for over-the-counter human use", the toothpaste industry has been conducting animal caries tests on every fluoride-containing toothpaste introduced into the U.S. market since 1996.

Enamel protection: a comparison of marketed dentifrice performance against dental erosion.

Purpose: To determine the relative ability of various marketed toothpastes formulated with either stabilized stannous fluoride (SnF2), sodium fluoride (NaF), or sodium monofluorophosphate (SMFP) to protect human enamel against the initiation and progression of damage due to dietary acid attack, using a laboratory erosion cycling model.

Methods: Cores of ground and polished enamel from extracted human teeth were soaked in pooled, human saliva (pellicle formation) and then subjected to erosion cycling conditions that included exposure of tooth specimens to: (1) treatments in a 1:3 slurry (w/w) of toothpastes and saliva; and (2) acid challenges using either citric acid (Study 1) or both citric and phosphoric acids (Study 2). These acids represent potentially damaging acids found in common food and drinks.

Anticaries potential of a stabilized stannous-containing sodium fluoride dentifrice.

Purpose: To evaluate the anticaries potential of a stabilized stannous-containing sodium fluoride dentifrice relative to appropriate control products.

Methods: A series of in vitro studies was conducted using the following standard anticaries efficacy measures: (1) fluoride uptake; (2) pH cycling remineralization/inhibition of demineralization; and (3) surface microhardness. In each study, the stannous-containing sodium fluoride test dentifrice (1450 ppm F) was compared to a negative control dentifrice (0 ppm F) and a positive control fluoride dentifrice (either 1100 ppm F or 1450 ppm F).

Anticaries potential of commercial dentifrices as determined by fluoridation and remineralization efficiency.

Aim: The aim of this in vitro study was to investigate fluoride uptake in human enamel after use of commercially available toothpastes containing different fluoride compounds, or combinations of fluoride actives formulated into a single product, as a means of determining the efficiency of each formula for delivering caries preventing fluoride to demineralized (caries active) enamel.

Methods And Materials: Four test dentifrices and two controls were assessed and placed in groups as follows: Group 1: Lacer (Spain); Group 2: Positive control-USP Reference Standard 1100 ppm F; Group 3: Fluocaril Bi-Fluoré 250 (France); Group 4: Colgate Fluor Active (Denmark); Group 5: Elmex (France); and Group 6: A placebo (formulated the same as the USP Reference Standard toothpaste with the exception that it contained < 1 ppm F). Cores 3 mm in diameter were removed from erupted human enamel specimens (extracted by local oral surgeons for orthodontic reasons) and stored in 1% Thymol solution prior to use.