New Approaches to Caries Prevention and Control Silver Nitrate, Silver Diamine Fluoride And Xylitol

Silver Nitrate Silver has been used medicinal since 1,000 B.C. Silver nitrate is used in medicine today for its effective anti-microbial effect. Leaders in dentistry in the early part of the 20th Century, G.V. Black, W.D. Miller and Percy Howe, utilized silver nitrate to arrest active carious lesions. In the later 20th Century it fell in to disuse, potentially due to the emphasis on eradicating caries and restoring the tooth, not simply arresting the active caries process. The epidemic of dental caries in young children has prompted a reassessment of silver nitrate as a means of arresting dental caries in young children until that time at which children can cooperate for having he teeth restored.

Silver Nitrate Caries Arrestment Technique 25% Silver Nitrate (25% silver nitrate and 75% water); It is marketed as Advantage Arrest and is available from Henry Schein company at www.HenrySchein.com In article by Duffin (see course website for article) the technique of use calls for application of the silver nitrate to an active carious lesion, followed by placing 5% fluoride varnish over the treated lesion. Duffin suggests the placement of the fluoride varnish prevents contact of the silver nitrate with the soft tissue (it is caustic); provides a protective layer to prevent the silver nitrate from being immediately washed away by saliva; and adds the preventive effect of fluoride.

Application Technique Duffin recommends that the application be repeated at two, four, eight and twelve weeks, though caries arrestment can be expected after one-two applications.

Silver Diamine Fluoride In several countries of the world, notably Brazil and Japan, a compounded combination of silver nitrate and fluoride is being used to prevent dental caries, as well as to arrest lesions: silver diamine fluoride. Silver diamine fluoride has been approved by the FDA for use in the United States, but as treatment for dentinal hypersensitivity, so it is used “off-label.” A systematic review of the literature (Journal of Dental Research) supporting the efficacy of silver diamine fluoride is at the module’s webpage. An extensive article by Horst, et al. on a protocol for the use of silver diamine fluoride is at the module’s webpage. The CDT Code for billing is D1354.

Contraindications History of any pain from the tooth, indicating the lesion is approximating or has invaded the pulp. Lack of sound dentin between the lesion and the pulp. Evidence that the tooth is non-vital, such as presence of a parulis (gum boil).

Advantages and Disadvantages The carious lesion is arrested; though the structure, function, and esthetics of the tooth is not restored. Caries is prevented from invading the pulp with subsequent pain and loss of vitality of the pulp and the tooth requiring extraction. In a very young uncooperative child arresting “early childhood caries” can permit delaying restoration until the child is older and able to cooperate for restoration of the teeth. Currently, young children with dental caries who are uncooperative have to be treated under general anesthesia in a hospital or out patient surgical center. This is a very expensive setting. Use of silver nitrate or a silver diamine fluoride regime is “medical” rather than “surgical’ approach to treating caries.

Xylitol Xylitol, in the form or chewing gum or candy, is being used as a significant caries preventive agent in Europe, particularly in Scandinavia. Field trials in the late 1960s and early 1970 in Finland demonstrated a significant caries preventive effect from diets sweetened with Xylitol rather than sucrose. Xylitol is a sugar alcohol (polyol) with sweetness equal to table sugar, but with 40% fewer calories. A primary source of Xylitol is from the sap of birch trees. Xylitol is not fermented by plaque bacteria. Thus it reduces accumulation of plaque on the teeth. Plaque pH does not drop when xylitol sweetened gum is chewed, therefore remineralization is enhanced. In Finland, school children typically chew Xylitol chewing gum three times a day for five minutes as a caries preventive regimen.

Xylitol Dental caries is an infectious disease. Infants are typically infected with mutans streptococci from their mothers as a result of the exchange of saliva. Mothers with open carious lesions or poor oral hygiene infect their children earlier with the microorganism. The earlier the infection of infants the more vulnerable the child becomes to dental caries. It is desirable to reduce the mutans streptococci load in pregnant women. This is typically done by restoring carious teeth, rinsing with chlorohexidine, and the use of high potency topical fluoride.

Xylitol Xylitol reduces mutans strep counts; therefore, use of xylitol chewing gum by pregnant women is advocated as an additional preventive strategy in reducing transmission of from mother to infant. In one study, in which mothers chewed xylitol gum three times a day for three months before delivery, their children had significantly lower mutans steptococci counts than a control group, even up to six years of age…and significantly less caries experience than controls. Three articles on the use of Xylitol in preventing dental caries are at the module’s webpage.