Painting Teeth With Fluoride Varnish Is Effective Against Tooth Decay In Children

April 11, 2000

GAINESVILLE, Fla.—With the stroke of a brush coated with a new topical fluoride treatment, dentists can paint a lasting smile for children in an easy, safe and cost-effective way, a new University of Florida study shows.

New to the United States, the product called sodium fluoride varnish has a higher concentration of fluoride than current gels, foams, rinses and pastes, but is less toxic to children because less of the product is swallowed during application.

“Fluoride varnish quickly adheres to teeth and over time is slowly released to the tooth surface, promoting tooth remineralization,” said Dr. Jaana Autio, a UF College of Dentistry assistant professor of pediatric dentistry, who studied the effectiveness of one varnish in a group of Head Start children aged 3 to 5.

Autio, the first researcher to study the effect fluoride varnish has on cavity progression in primary teeth, reported her findings April 6 at the International Association for Dental Research conference in Washington D.C.

In the study, Autio said the UF researchers divided 222 Alachua County, Fla., Head Start children into a group that received the fluoride varnish and a control group that received a common fluoride gel. In 1997, the Food and Drug Administration approved Duraphat, the brand of varnish used in the study and manufactured by Colgate-Palmolive, as a fluoride treatment for people with hypersensitive teeth. Other fluoride varnish studies are under way to determine their effectiveness as anti-cavity agents.

“We studied the children over a nine-month period in the schools, applying the varnish at the start of the study and at a four-month interval. We found that at the end of the study, the progression of dental cavities had reversed (remineralized) in more than 80 percent of the test group and 37 percent in the control group,” Autio said. “The varnish was clearly more beneficial to the children than the gel and reduced the need for expensive fillings.”

Because of the high concentration of fluoride (22,600 parts per million compared to toothpaste which has 1,000 to 1,400 ppm) Duraphat is available only to dental professionals. The cost is comparable to current fluoride gels and foams.

Duraphat comes in a small tube and is painted on the teeth. The yellowish tint of the varnish allows dentists to see where the product has been applied. Saliva enables it to adhere to teeth rapidly. After one hour, children can rinse their mouth. The next morning, they should resume their normal brushing routine. Applying the varnish takes less than two minutes, making it ideal for patients who are anxious or who have special needs. The likable taste also is a drawing point, but for parents and the dental profession the two main benefits are its effectiveness in preventing the need for fillings and crowns, as well as the decreased risk of fluoride toxicity and fluorosis.

“Toxicity and its effects such as nausea are always a concern with children under 6. Previous studies have shown that fluoride in patients’ blood plasma is lowest among fluoride varnish users than users of other topical treatments. Less is swallowed,” Autio said.

Dental fluorosis, a harmless cosmetic discoloring or mottling of the enamel, is visible by chalky white specks and lines or pitted and brown stained enamel on developing teeth. Fluorosis occurs when children ingest too much fluoride during the period of enamel formation (before teeth appear in the mouth) in children usually under the age of 6.

Fluoride varnish has a long history of use by dentists throughout Europe as an anti-cavity treatment in adults and children. Autio, at UF since 1997, used the product routinely in her practice in Finland. Along with other American dentists and organizations such as the American Dental Association, she thinks that all children can benefit from use of the varnish, especially children from low-income families.

“Despite the decline in the incidence of dental cavities in the United States, decay and cavities remain a problem among the nation’s poor children,” Autio said.

UF’s pediatric department provides dental screenings for several Florida Head Start programs. Autio and co-researcher Dr. Frank Courts, both advocates of providing dental care to low-income children, believe the easy application and positive results of varnish use makes it ideal to be administered routinely in the school system.

“Prevention is key,” said Courts, associate professor and chair of pediatric dentistry. “The earlier we can reach children following the eruption of their primary teeth, the better.”

Autio and Courts’ initial study results indicate varnishes may soon be the preferred anti-cavity topical agent used for children.

Huw F. Thomas, professor and chair of pediatric dentistry at the University of Texas at San Antonio, who heard Autio’s presentation at the conference, said the UF study is significant.

“The results of this study are extremely important in highlighting the effectiveness of this mode of treatment in a high-risk population.” Thomas said. “Now we have a significant tool to address disease prevention in susceptible children and afford them a better quality of life.”

Auito says that she is planning to conduct a two-year study using Head Start children to determine the effectiveness of the varnish over an extended period of time.