Stannous fluoride dentifrices

Currently accepted dentifrices contain sodium mono-fluorophosphate, sodium fluoride, or, less frequently, stannous fluoride, all of which reduce caries by approximately 25% when used daily. In some clinical studies, stannous fluoride dentifrices stained teeth, particularly in pits and fissures. This stain is related to the tin in this compoimd, which adheres to plaque. The significance of this staining and its esthetic problems have resulted in a decreased usage in dentifrices. Stannous fluoride dentifrices are marketed in a plastic container because a reaction of stannous ions at an acid pH occurs when conventional soft metal tubes are used. 

Dentifrices containing stannous fluoride as an active ingredient are no longer widely marketed however, these formulations were the first to be evaluated for caries-reducing properties. Effectiveness in caries reduction varied from 23 to 34%). One stannous fluoride dentifrice containing a patented stabilized form of stannous fluoride is marketed with a claim of both caries and gingivitis reduction. However, this product is not ADA accepted. 

Stannous fluoride is used in dentifrices and dental preparations. The OSHA permissible exposure limit (44) and ACGIH (45) estabUshed TLV for fluoride is 2.5 mg/m of air. 

The principal commercial use of stannous fluoride is in toothpaste formulations and other dental preparations, eg, topical solutions, mouthwash, chewing gum, etc, for preventing demineralization of teeth (21—23) (see Dentifrices). 

Eluoride added to a compatible dentifrice base at a level of 1000 ppm has been clinically proven to reduce the incidence of dental caries by about 25% on average, even in areas where the water supply is fluoridated (4). Elevation to 1500 ppm increases the protection. Sources of fluoride approved for use in dentifrices are sodium fluoride [7681-49-4] (0.22%), sodium monofluorophosphate (0.76%), and stannous fluoride [7783-47-3] (0.41%). The Eood and Dmg Administration regulates fluoridated dentifrices as dmgs and has estabUshed parameters for safe and effective products. CompatibiUty of the fluoride with the abrasive is an important requirement. 

Sodium fluoride as an ingredient in dentifrices has been the subject of a number of clinical investigations. Recent studies of sodium fluoride dentifrices formulated to ensure ready availability of fluoride ions have shown anticaries benefits similar to those obtained in clinical caries trials with dentifrices containing stannous fluoride and sodium monofluorophosphate. 

Currently, there are no ADA-approved, over-the-counter dentifrices containing stannous fluoride. However, there are a number of ADA accepted stannous fluoride prescription products approved for application by the dentist or by the patient. 

Solutions of 8% stannous fluoride have been used to reduce caries. As with the other agents, the teeth are polished, dried, and isolated, and a 4-min application follows. The disadvantages of this solution are that it must be freshly prepared, some tooth discoloration (as discussed under dentifrices) has occurred, and it has an unpleasant taste that is difficult to mask. 

A number of studies have reported that topical fluoride application may reduce dental hypersensitivityJ ° These results have been found when concentrated dosage forms have been applied ranging from 8% stannous fluoride gels to 33.3% sodium fluoride paste. It has been shown that commercial dentifrices containing stannous fluoride may also decrease dental hypersensitivity. Also, a combination of stannous fluoride and potassium nitrate is marketed by one manufacturer to reduce sensitivity. Varnishes containing sodium fluoride have also been shown to reduce dental hypersensitivity. 

The greatest success occurs with dentifrices containing 5% potassium nitrate (e.g., Sensodyne , Rembrandt, Crest, AquaFresh , and Protect ), and some fluoride-containing dentifrices. Recently, a dentifrice containing potassium nitrate and stannous fluoride has been introduced to treat this problem (Colgate). 

Segal, A.H. Stiff, R.H. George, W.A. Picozzi, A. Cario-static effect of a stannous fluoride-containing dentifrice on children two-year report of a supervised toothbrushing study. J. Oral Ther. Pharmacol. 1967, 4 (3), 175-180. 

The general population is exposed to fluoride through consumption of drinking water, foods, and dentifrices, primarily in the form of sodium fluoride and stannous fluoride. Populations exposed to... 

A few well-controlled clinical studies suggested a potential plaque-inhibiting effect for dentifrices containing staimous fluoride. However, these results were most likely due to the stannous ion rather than to fluoride the positive charge of the stannous ion may interfere with bacterial membrane function, bacterial adhesion, and glucose uptake, thereby inhibiting the formation of plaque. 

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