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About fluoride and sealants


To prevent and control dental decay, fluorides are effective and safe. Water fluoridation is the most cost effective public health means of improving the oral health of a population. Approximately 75% of King County's population is on fluoridated water systems.

Fluoride's greatest effect comes from its topical interaction with the tooth surface and daily use of fluoride toothpaste is an important step in preventing decay. Topical fluoride for home use is available in other forms that a dental professional may recommend. Additionally, a dental professional may apply high-concentration fluoride treatments as a preventive treatment. These fluoride treatments come as gels, foams or varnishes.


Dental sealants are thin plastic coatings that protect the pits and grooves in teeth and they are mainly used on the chewing surfaces of molars. The pits and grooves create natural hiding places for the bacteria because they are impossible to clean. Consequently, dental sealants prevent the bacteria from colonizing these areas.

Sealants are painted on the teeth so there is no drilling involved. The tooth is first prepared by using a small amount of a special acid, which is then rinsed away and the tooth surface thoroughly dried. Next, the sealant materials are painted on the tooth which are cured on their own or with an ultraviolet light. If a sealant is retained, the surface protected by the sealant will remain decay free.