The recommendations come from the U.S. Preventive Services Task Force (USPSTF), a government-backed panel.
Only one in four preschool children is seeing a dentist, but most see a primary care clinician, Dr. Michael LeFevre told Reuters Health. Primary care clinicians can play an important complementary role in helping dentists keep childrens teeth healthy.
A family physician from the University of Missouri School of Medicine in Columbia, LeFevre chairs the USPSTF.
The panel declined to state how often doctors should apply fluoride varnish to infants teeth, saying research is inconclusive.
Pediatric dentist Dr. Mary Hayes welcomed the help from pediatricians, family doctors and nurse practitioners.
Its a good thing that dentistry and medicine are working hand in hand trying to attack decay in kids mouths, she told Reuters Health. Hayes is an American Dental Association spokeswoman and was not involved with the new recommendations.
In addition to applying fluoride varnish to all baby teeth, the task force continues to urge doctors to prescribe oral fluoride supplements to infants who have not had fluoride added to their drinking water. Supplements come in daily doses of drops, tablets or lozenges.
In an effort to prevent tooth decay, fluoride was first added to the water supply in Grand Rapids, Michigan, in 1945. Since then, communities throughout the U.S. have debated whether to add the naturally occurring mineral to public water systems.
About two-thirds of Americans currently drink water from fluoridated community systems, according to the Centers for Disease Control and Prevention.
The task force last updated its recommendations on prevention of tooth decay in preschool-aged children 10 years ago.
In 2004, it said primary care doctors should prescribe oral fluoride to babies whose water had not been fluoridated starting at six months old.
Evidence at the time showed the benefit of reducing the risk of dental cavities with fluoride outweighed possible harms, including fluorosis, a condition that discolors teeth and can pit the enamel.
LeFevre and Hayes both said the task force thoroughly examined fluoride risks in formulating the new recommendations. But Dr. Philippe Grandjean, from the Harvard School of Public Health in Boston, told Reuters Health in an email that the panel appears not to have considered brain-related risks from fluoride exposure.
In 2012, Grandjean found that 26 of 27 studies on intelligence tests in fluoride-exposed children showed an IQ deficit linked to increased fluoride. All but two of the studies were conducted in China, where water fluoride levels were sometimes much higher than is typical in the U.S.
LeFevre added in an email, The Task Force recommendation for supplements when the water supply is deficient in fluoride is based on the benefits and harms found in trials of supplementation in those selected circumstances. The Task Force did not examine the epidemiologic studies related to fluoridation of water.
Dental varnish is not expected to have much systemic absorption, he wrote.
Grandjean, who was not involved in the new recommendations, said he could not assess possible risks of water fluoridation in the U.S. and called for research to clarify fluorides role in potential adverse effects on brain development.
In 2011, the U.S. Department of Health and Human Services lowered recommended fluoride limits in water, saying too large a dose of the mineral, which is also found in toothpaste and mouth rinses, may have damaged some childrens teeth.
The new task force report, published in Pediatrics, points out that about 42 percent of children between two and 11 years old get cavities in their baby teeth. That percentage decreased from the early 1970s until the mid-1990s, when tooth decay began increasing again, particularly in preschool-aged children.
Hayes said she regularly sees children with mouths full of unhealthy teeth in her Chicago pediatric dental practice. Just this week she said she treated a four-year-old girl with two front teeth that needed to be extracted, six molars that needed crowns, two molars that needed fillings and four that needed partial root canals.
The child had been drinking four cups of soda per day, Hayes said. Now, at Hayes insistence, she drinks just milk and water.
Renee Sharp, research director for the Environmental Working Group, a research and advocacy group, said she was more comfortable with the new recommendation on professionally applied fluoride varnish than she was with the recommendation on parent-administered fluoride drops for infants.
She is based in Oakland, California, and was not involved with the guidelines.
We certainly have concerns with the drops because its so imprecise, and it would be so easy to overexpose a child to fluoride, Sharp said.
The task force recommendations do not address educating parents about optimal dietary and other health practices for their childrens oral hygiene. The guidelines do call for more research on the question.
The panel members also conclude there is not enough evidence to recommend that primary care doctors routinely examine the mouths of their preschool-aged patients.