Procedures
Topical fluoride
Procedure overview
Learn about the dental procedure, when it is generally prescribed, and other information which can increase your knowledge of the topic.
Alternate terms: Fluoride.
Fluoride is a naturally occurring element which helps to harden tooth enamel and make it more resistant to acid exposure. It helps protect against cavities and can reduce tooth sensitivity.
Topical fluoride application is generally recommended twice a year for children through their adolescent years to help prevent cavities. A dentist is the best person to assess the patient's individual risk for cavities, and the developmental status of the patient's teeth.
Topical fluoride supplementation is also recommended in patients who suffer from dry mouth ("xerostomia"), generalized gum recession, and sensitive teeth.
Learn more: Diagnoses › Xerostomia
Figure 1: This electron micrograph shows how porous tooth enamel is. The dark spots are pores in the enamel crystal, which make the tooth vulnerable to acid attack. (Source: Journal of Islamic Academy of Sciences).
Figure 2: This scanning electron micrograph shows how flouride ions (see arrows) help to fill in voids in the crystal structure of enamel, especially the smaller pores. The fluoride ion displaces a portion of the enamel crystal that has a similar shape, but is slightly smaller than fluoride. The result is a crystal which is more dense, less porous, and more resistant to acids. (Source: Journal of Islamic Academy of Sciences).
When fluoride is incorporated in the diet of young children (mainly through water fluoridation programs), the entire enamel thickness may be less porous. When applied topically, only the surface enamel benefits. However, surface fluoridation of the teeth is believed to be the most effective at reducing cavities.
Additional information
The tooth-protecting attribute of fluoride was first noted in Colorado, parts of which have naturally occurring fluoride levels several times the recommended therapeutic (i.e. effective) level. Around 1901, many people in the Colorado Springs area were noted by Dr. Frederick S. McKay to have brownish stains and mottling of their teeth ("particularly the uppers"). The issue was studied at length for several decades by several leading dental researchers of the time, and many years later was traced to chronic overexposure to fluoride. This condition, known as fluorosis, was referred to at the time as "Colorado Brown Stain", and caused quite a stir in dental academic circles of the era.
During the studies, this same population of people were found to have very little tooth decay, and the relationship between fluoride and acid-resistant enamel was deduced. Since then, appropriate therapeutic levels of fluoridation have been established that offer the protections of fluoride without causing the mottling and stain of the teeth.
Fluoridation of the drinking water began in the late 1940s, and according to the U.S. Centers for Disease Control (CDC), has been one of the most successful public health measures ever implemented in terms of dollars saved on treatment of tooth decay (a bacterial illness). Not everyone has access to publicly fluoridated water, however, and your dentist or pediatrician may recommend daily fluoride supplementation for your child while their teeth are developing.
View the CDC's most up-to-date daily fluoride supplementation schedule.
Per current guidelines, "ideally" fluoridated drinking water contains from 0.7 to 1.4 parts per million (ppm) fluoride ion, depending upon how arid the climate and how much water people need to drink in order to keep their body hydrated. People in drier climates drink more water, and therefore need less fluoride in the water. Fluoride toothpastes typically contain about 1,500 ppm fluoride, while topically applied fluoride from the dentist has about 15,000 ppm. Prescription strength fluoride gels and toothpastes contain about 5,000 ppm fluoride.
Permanent (adult) tooth development begins during fetal gestation, with the six-year molars and incisor tooth crowns nearly fully formed at birth (even though those teeth do not begin to move into the mouth for another five to seven years on average). The development of tooth enamel continues until the adolescent years, when the third molar ("wisdom tooth") crowns near developmental completion. In some patients, third molar formation is apparent on head radiographs (panoramic and cephalometric) as early as age 8 or 9. In some, however, they are not noted until the teen-age years. If the wisdom teeth are to be retained (not removed), they should benefit from fluoridation through the completion of development, at least into the middle teen-age years on average.
Fluoride Overdose
If you think your child has swallowed too much fluoride:
- If they are not allergic, give your child a glass of milk. Calcium present in the milk will form a chemical bond to the fluoride producing calcium fluoride salt which is excreted.
- Call a poison control center.
