Importance Dental caries is the most common chronic disease in children in the US. According to the 2011-2016 National Health and Nutrition Examination Survey, approximately 23% of children aged 2 to 5 years had dental caries in their primary teeth. Prevalence is higher in Mexican American children (33%) and non-Hispanic Black children (28%) than in non-Hispanic White children (18%). Dental caries in early childhood is associated with pain, loss of teeth, impaired growth, decreased weight gain, negative effects on quality of life, poor school performance, and future dental caries.
Objective To update its 2014 recommendation, the US Preventive Services Task Force (USPSTF) commissioned a systematic review on screening and interventions to prevent dental caries in children younger than 5 years.
Population Asymptomatic children younger than 5 years.
Evidence Assessment The USPSTF concludes with moderate certainty that there is a moderate net benefit of preventing future dental caries with oral fluoride supplementation at recommended doses in children 6 months or older whose water supply is deficient in fluoride. The USPSTF concludes with moderate certainty that there is a moderate net benefit of preventing future dental caries with fluoride varnish application in all children younger than 5 years. The USPSTF concludes that the evidence is insufficient on performing routine oral screening examinations for dental caries by primary care clinicians in children younger than 5 years and that the balance of benefits and harms of screening cannot be determined.
Recommendation The USPSTF recommends that primary care clinicians prescribe oral fluoride supplementation starting at age 6 months for children whose water supply is deficient in fluoride. (B recommendation) The USPSTF recommends that primary care clinicians apply fluoride varnish to the primary teeth of all infants and children starting at the age of primary tooth eruption. (B recommendation) The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of routine screening examinations for dental caries performed by primary care clinicians in children younger than 5 years. (I statement)
See the Summary of Recommendations figure.
Dental caries is the most common chronic disease in children in the US.1–3 According to the 2011-2016 National Health and Nutrition Examination Survey, approximately 23% of children aged 2 to 5 years had dental caries in their primary teeth.4 Prevalence is higher in Mexican American children (33%) and non-Hispanic Black children (28%) than in non-Hispanic White children (18%).5 Dental caries in early childhood is associated with pain, loss of teeth, impaired growth, decreased weight gain, negative effects on quality of life, poor school performance, and future dental caries.1
USPSTF Assessment of Magnitude of Net Benefit
The US Preventive Services Task Force (USPSTF) concludes with moderate certainty that there is a moderate net benefit of preventing future dental caries with oral fluoride supplementation at recommended doses in children 6 months or older whose water supply is deficient in fluoride.
The USPSTF concludes that the evidence is insufficient on performing routine oral screening examinations for dental caries by primary care clinicians in children younger than 5 years and that the balance of benefits and harms of screening cannot be determined.
See the Table for more information on the USPSTF recommendation rationale and assessment and the eFigure in the Supplement for information on the recommendation grade. See the Figure for a summary of the recommendation for clinicians. For more details on the methods the USPSTF uses to determine the net benefit, see the USPSTF Procedure Manual.6
Patient Population Under Consideration
This recommendation applies to asymptomatic children younger than 5 years.
Assessment of Risk
All children are at potential risk for dental caries. There are no validated screening tools to determine which children are at higher risk for dental caries; however, a number of individual factors elevate risk. Higher prevalence and severity of dental caries are found among low-income and certain racial and ethnic (eg, Black and Mexican American) populations.1 Risk factors for dental caries in children are multifactorial. Biological risk factors include cariogenic bacteria, developmental defects of tooth enamel, and low saliva flow rates. Social determinants of health (nonbiological factors) that are associated with increased caries risk include access to dental care, low socioeconomic status, personal and family oral health history, dietary habits (especially frequent intake of dietary sugars in foods and beverages), fluoride exposure, and oral hygiene practices.1,7,8
Interventions to Prevent Dental Caries
Oral fluoride supplementation prevents dental caries in patients with deficient water fluoridation (<0.6 parts fluoride per million parts water [ppm F]).9–11 Topical fluoride is applied as a varnish with a small brush in young children (typically available as 5% sodium fluoride [2.26% fluoride]). The use of topical fluoride for prevention of caries is off-label.12–15
Timing and Dosage
No studies specifically addressed the dosage and timing of oral fluoride supplementation in children with inadequate water fluoridation.
No studies directly assessed the appropriate ages at which to start and stop the application of fluoride varnish. However, given the mechanism of action of this intervention, benefits are likely to accrue starting at the time of primary tooth eruption. In studies, fluoride varnish was most commonly administered as 5% sodium fluoride, every 6 months.1
Additional Tools and Resources
There are several related tools and resources that may help clinicians implement this recommendation:
The Community Preventive Services Task Force recommends fluoridation of community water sources to reduce dental caries.16
The Community Preventive Services Task Force recommends school-based dental sealant delivery programs to prevent caries.17
The Centers for Disease Control and Prevention’s Oral Health resources include “My Water’s Fluoride,” a tool to find information about a local water system’s fluoridation status.18
The Health Resources and Services Administration’s website contains various oral health program resources, including the “Bright Futures: Oral Health–Pocket Guide, 3rd edition,” an overview of oral health prevention and interventions (https://mchb.hrsa.gov/maternal-child-health-topics/child-health).19
Suggestions for Practice Regarding the I Statement
In deciding whether to routinely perform screening examinations for dental caries in children from birth to age 5 years, clinicians should consider the following.
Potential Preventable Burden
Dental caries is a common chronic disease that can cause pain and diminished quality of life.4 According to the National Health and Nutrition Examination Survey, the prevalence of dental caries increased from 24% to 28% between 1988-1994 and 1999-2004; the prevalence was approximately 23% from 2011 to 2016.5 Seventeen percent of children living below the poverty threshold had untreated caries in 2011 to 2014. Dental-related concerns lead to the loss of more than an estimated 50 million school hours each year.3
Primary care screening examinations for dental caries in children from birth to age 5 years are noninvasive and not likely to cause serious harms.
A 2009 study demonstrated that only about half of pediatricians reported examining the teeth of more than half of their patients aged 0 to 3 years, and few (4%) reported regularly applying fluoride varnish.20
Update of Previous USPSTF Recommendation
This is an update of the 2014 USPSTF recommendation statement, in which the USPSTF similarly recommended that primary care clinicians prescribe oral fluoride supplementation starting at age 6 months for children whose water supply is deficient in fluoride (B recommendation) and that primary care clinicians apply fluoride varnish to the primary teeth of all infants and children starting at the age of primary tooth eruption (B recommendation). The USPSTF found insufficient evidence to assess the balance of benefits and harms of routine screening examinations for dental caries performed by primary care clinicians in children younger than 5 years (I statement).21
Scope of Review
The USPSTF commissioned a systematic review1,22 to update its 2014 recommendation on screening and interventions to prevent dental caries in children younger than 5 years. The review focused on screening for caries, assessment of risk for future caries, and the effectiveness of various interventions (eg, caregiver/guardian oral health education, preventive medication, or referral to a dental health care professional) that have possible benefits in preventing caries. The USPSTF limited its consideration of caries screening and prevention by primary care clinicians to infants and preschool-aged children. The rationale for this decision was that primary care clinicians are more likely than dental health care professionals to have contact with children younger than 5 years in the US; this situation changes as children reach school age and beyond as opportunities to provide dental services in school settings become available. In addition, as children grow older, dental professionals use sealants rather than fluoride varnish. As such, the USPSTF limited its review of the evidence of preventive interventions for dental caries to this age group. This recommendation should not be construed to imply that preventive interventions for dental caries should cease after age 5 years.
Accuracy of Screening
One good-quality cohort study (n?=?258) in children younger than 36 months found that a primary care pediatrician examination after 2 hours of training was associated with a sensitivity of 0.76 and specificity of 0.95 for identifying a child with 1 or more cavities, a sensitivity of 0.49 and specificity of 0.99 for identifying a tooth with a cavity, and a sensitivity of 0.63 and specificity of 0.98 for identifying children in need of a dental referral, compared with a pediatric dentist evaluation.1,22 A fair-quality study in 110 children aged 18 to 36 months found that an oral examination by a pediatrician had a sensitivity of 1.0 and a specificity of 0.87 for identifying nursing caries.1,22
One fair-quality study (n?=?1681) found that a novel caries risk assessment tool administered by health visitor nurses in children age 1 year was associated with sensitivity of 0.53 and specificity of 0.77 for predicting any dentin lesions at age 4 years and sensitivity of 0.65 and specificity of 0.69 for predicting presence of 3 or more dentin lesions.1,22
Effectiveness of Screening
No studies compared clinical outcomes between children younger than 5 years who were screened and not screened for dental caries by primary care clinicians.
Harms of Screening
No studies reported harms of screening in children younger than 5 years who were screened and not screened for dental caries by primary care clinicians.
Effectiveness of Preventive Interventions
The USPSTF considered 15 trials (2 good quality and the rest fair quality). The number of participants ranged from 123 to 2536 (total N?=?9541). Trials were conducted in the US, Europe, Brazil, China, and Iran, and 2 trials were in Aboriginal communities in Australia and Canada. The mean age of enrolled children was 1 year to younger than 2 years in 6 trials and 2 years to younger than 5 years in 7 trials; 1 trial did not report mean age but enrolled children aged 6 months to 5 years.1,22 Three trials were conducted in preschool or daycare settings and the others were conducted in clinics. Fourteen trials evaluated children classified as higher risk based on low socioeconomic status, high community prevalence of caries, high baseline caries burden (based on high proportion of children with caries at baseline), or low rates of oral health behaviors (eg, tooth brushing with fluoride toothpaste).1,22
The USPSTF found 1 randomized trial and 4 nonrandomized trials that compared dietary fluoride supplementation with no supplementation in settings with a water fluoride level less than 0.6 ppm F and found decreased caries incidence. The percentage reduction in incidence ranged from 48% to 72% for primary teeth and 51% to 81% for primary tooth surfaces.1,22
The USPSTF found 15 trials (n?=?9541) that demonstrated that topical fluoride was associated with decreased caries increment (13 trials; n?=?5733; mean difference, –0.94 [95% CI, –1.74 to –0.34]; I2?=?86%) and decreased likelihood of incident caries (12 trials; n=8177; risk ratio, 0.80 [95% CI, 0.66 to 0.95]; I2?=?79%; absolute risk difference, –7% [95% CI, –12% to –2%]) vs placebo or no varnish.1,22 The majority of the trials were conducted in higher-risk populations or settings.1,22 “High risk” was defined by low socioeconomic status, high caries burden, or suboptimal oral health practices (eg, inadequate tooth brushing). There was no difference in benefits of topical fluoride related to whether trials were conducted in settings with adequate fluoridation.1,22 Evidence on other preventive interventions was limited (ie, xylitol and silver diamine fluoride).1,22
The USPSTF found no studies that directly evaluated the effect of referral by a primary care clinician to a dental health care professional on caries incidence. One fair-quality retrospective cohort study (n?=?19?888) and 1 fair-quality observational study (n?=?11?394) of children enrolled in Medicaid found no difference in rates of subsequent dental procedures between earlier and later first preventive dental visits among children with no caries at baseline.1,22 Four fair-quality observational studies (n?=?61?194) of children enrolled in Medicaid found that patients receiving a preventive dental visit were more likely to receive subsequent caries treatment than patients who saw a primary care clinician. However, the results were subject to confounding because children who saw a dental health care professional might have had a greater indication for dental services. The studies were also not designed to determine the referral source or effects of dental referral from primary care vs no referral.1,22
The USPSTF found limited evidence on educational or counseling interventions. One new fair-quality trial (n?=?104) found that oral health education for mothers of caries-free children aged 12 to 36 months was associated with reduced risk of incident dental caries vs usual care at 6 months (13.5% vs 34.7%; risk ratio, 0.39 [95% CI, 0.18 to 0.85]).1,22
Harms of Preventive Interventions
Severe fluorosis (for example, as demonstrated by discoloration and pitted or rough enamel surface of the teeth) is uncommon, with a prevalence of less than 2%.1,22 Nineteen observational studies showed an association between ingestion of systemic fluoride in early childhood and enamel fluorosis of permanent teeth.1,22 Four trials (n?=?4141) found no differences in risk of fluorosis or any other adverse event between fluoride varnish and placebo or no varnish.1,22
How Does Evidence Fit With Biological Understanding?
Systemic fluoride becomes incorporated into tooth structures during their formation. If fluoride is ingested repeatedly during tooth development, it is deposited throughout the tooth surface and provides protection against caries. Topical fluoride treatments, such as varnishes, help protect teeth that are already present. In this method, fluoride is incorporated into the surface layer of the teeth, making them more resistant to decay. Systemic fluoride also provides some measure of topical effects, as it is found in the saliva and bathes the teeth. Thus, providing both systemic and topical fluoride to children during tooth development fits with the biological understanding of the protective actions of fluoride against dental decay. All children with erupted teeth can potentially benefit from the periodic application of fluoride varnish, regardless of the levels of fluoride in their water. Although the evidence to support fluoride varnish is drawn from higher-risk populations, the provision of fluoride varnish to all children is reasonable because the prevalence of risk factors is high in the US population.23–25
Response to Public Comment
A draft version of this recommendation statement was posted for public comment on the USPSTF website from May 11, 2021, to June 7, 2021. Several respondents shared concerns about risk of fluoride toxicity and barriers to primary care clinician fluoride prescriptions, including knowledge of local water fluoridation status. In response, the USPSTF added timing and dosage information to the Practice Considerations section and updated the Harms of Preventive Interventions section. The USPSTF also expanded the Additional Tools and Resources section to include a tool from the Centers of Disease Control and Prevention that may aid clinicians in identifying the amount of fluoride in a local water system. Comments were also received requesting that the USPSTF recommend that primary care clinicians provide other interventions such as health education. The USPSTF describes the evidence it reviewed on health education in the Supporting Evidence section.
Research Needs and Gaps
More studies are needed that address the following:
Research is needed to validate the accuracy and utility of caries risk assessment instruments for use in primary care settings and to determine how referral of young children for dental care by primary care clinicians affects caries outcomes.
Further research would also be helpful to confirm the benefits of fluoride varnish among lower-risk children.
Research is needed to understand the benefit or harm of routine screening by primary care clinicians on caries outcomes in children younger than 5 years.
Future studies on risk assessment and preventive interventions should enroll sufficient numbers from certain racial and ethnic populations (eg, Black and Hispanic children) to understand the benefits and harms of interventions in these specific groups.
Research is needed to identify effective preventive measures in economically disadvantaged children.
Research is needed to identify effective oral health educational and counseling interventions for parents and caregivers/guardians of young children.
Studies are also needed on the benefits and harms of silver diamine fluoride for the prevention of caries in young children.
Recommendations of Others
The American Academy of Pediatrics (AAP) recommends that pediatricians perform oral health risk assessments on all children at every routine well-child visit beginning at age 6 months. The AAP also recommends fluoride varnish application according to the AAP/Bright Futures Periodicity Schedule (applied at least once every 6 months for all children and every 3 months for children at high risk for caries) and dietary fluoride supplements for all children who do not have an adequate supply of fluoride in their primary drinking water. The AAP recommends a first dental visit by age 1 year.25–27
The American Dental Association recommends that children be seen by a dentist within 6 months of eruption of the first tooth and no later than age 12 months. It also recommends 2.26% fluoride varnish for children younger than 6 years who are at risk for developing dental caries.28
The Centers for Disease Control and Prevention recommends that fluoride supplements may be best prescribed to children at high risk for dental caries whose drinking water lacks adequate fluoridation.24
The American Academy of Pediatric Dentistry states that fluoride dietary supplements should be considered for children at risk for caries who drink fluoride-deficient (<0.6 ppm F) water. It also states that children at increased risk for caries should receive a professional fluoride treatment (eg, 5% sodium fluoride varnish or 1.23% acidulated phosphate fluoride) every 6 months.29,30
Accepted for Publication: October 26, 2021.
Conflict of Interest Disclosures: Authors followed the policy regarding conflicts of interest described at https://www.uspreventiveservicestaskforce.org/Page/Name/conflict-of-interest-disclosures. All members of the USPSTF receive travel reimbursement and an honorarium for participating in USPSTF meetings.
Funding/Support: The USPSTF is an independent, voluntary body. The US Congress mandates that the Agency for Healthcare Research and Quality (AHRQ) support the operations of the USPSTF.
Role of the Funder/Sponsor: AHRQ staff assisted in the following: development and review of the research plan, commission of the systematic evidence review from an Evidence-based Practice Center, coordination of expert review and public comment of the draft evidence report and draft recommendation statement, and the writing and preparation of the final recommendation statement and its submission for publication. AHRQ staff had no role in the approval of the final recommendation statement or the decision to submit for publication.
Disclaimer: Recommendations made by the USPSTF are independent of the US government. They should not be construed as an official position of AHRQ or the US Department of Health and Human Services.
Additional Contributions: We thank Iris Mabry-Hernandez, MD, MPH, and Sheena Harris, MD, MPH (AHRQ), who contributed to the writing of the manuscript, and Lisa Nicolella, MA (AHRQ), who assisted with coordination and editing.
Additional Information: The US Preventive Services Task Force (USPSTF) makes recommendations about the effectiveness of specific preventive care services for patients without obvious related signs or symptoms. It bases its recommendations on the evidence of both the benefits and harms of the service and an assessment of the balance. The USPSTF does not consider the costs of providing a service in this assessment. The USPSTF recognizes that clinical decisions involve more considerations than evidence alone. Clinicians should understand the evidence but individualize decision-making to the specific patient or situation. Similarly, the USPSTF notes that policy and coverage decisions involve considerations in addition to the evidence of clinical benefits and harms. Published by JAMA®–Journal of the American Medical Association under arrangement with the Agency for Healthcare Research and Quality (AHRQ). ©2021 AMA and United States Government, as represented by the Secretary of the Department of Health and Human Services (HHS), by assignment from the members of the United States Preventive Services Task Force (USPSTF). All rights reserved.
- Chou R, Pappas M, Dana T, Selph S, Hart E, Schwarz E. Screening and Prevention of Dental Caries in Children Younger Than Five Years of Age: A Systematic Review for the US Preventive Services Task Force. Evidence Synthesis No. 210. Agency for Healthcare Research and Quality; 2021. AHRQ publication 21-05279-EF-1.
- National Center for Health Statistics. Healthy People 2010: final review. Centers for Disease Control and Prevention. Published 2012. Accessed October 13, 2021. https://www.cdc.gov/nchs/data/hpdata2010/hp2010_final_review.pdf
- US Department of Health and Human Services. Oral Health in America: A Report of the Surgeon General. National Institute of Dental and Craniofacial Research. Published 2000. Accessed April 27, 2021. https://www.nidcr.nih.gov/sites/default/files/2017-10/hck1ocv.%40www.surgeon.fullrpt.pdf
- Centers for Disease Control and Prevention. Oral Health Surveillance Report: Trends in Dental Caries and Sealants, Tooth Retention, and Edentulism, United States, 1999-2004 to 2011-2016. Centers for Disease Control and Prevention; 2019.
- Dye BA, Mitnik GL, Iafolla TJ, Vargas CM. Trends in dental caries in children and adolescents according to poverty status in the United States from 1999 through 2004 and from 2011 through 2014. J Am Dent Assoc. 2017;148(8):550-565. doi:10.1016/j.adaj.2017.04.013PubMedGoogle ScholarCrossref
- Procedure Manual. US Preventive Services Task Force. Published May 2021. Accessed October 13, 2021. https://uspreventiveservicestaskforce.org/uspstf/about-uspstf/methods-and-processes/procedure-manual
- Caufield PW, Griffen AL. Dental caries: an infectious and transmissible disease. Pediatr Clin North Am. 2000;47(5):1001-1019. doi:10.1016/S0031-3955(05)70255-8PubMedGoogle ScholarCrossref
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- Dooley D, Moultrie NM, Heckman B, Gansky SA, Potter MB, Walsh MM. Oral health prevention and toddler well-child care: routine integration in a safety net system. Pediatrics. 2016;137(1):e20143532. doi:10.1542/peds.2014-3532PubMedGoogle Scholar
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- Garcia RI, Gregorich SE, Ramos-Gomez F, et al. Absence of fluoride varnish-related adverse events in caries prevention trials in young children, United States. Prev Chronic Dis. 2017;14:E17. doi:10.5888/pcd14.160372PubMedGoogle Scholar
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- Policy on the use of xylitol in pediatric dentistry. American Academy of Pediatric Dentistry. Revised 2020. Accessed October 13, 2021. https://www.aapd.org/research/oral-health-policies–recommendations/use-of-xylitol/
- Dental caries (cavities): community water fluoridation. The Community Guide. Published April 2013. Accessed October 13, 2021. https://www.thecommunityguide.org
- Dental caries (cavities): school-based dental sealant delivery programs. The Community Guide. Published April 2013. Accessed October 13, 2021. https://www.thecommunityguide.org
- My water’s fluoride. Centers for Disease Control and Prevention. Last Reviewed July 20, 2021. Accessed October 13, 2021. https://nccd.cdc.gov/DOH_MWF/Default/Default.aspx
- Child health. Health Resources and Services Administration. Last reviewed September 2021. Accessed October 19, 2021. https://mchb.hrsa.gov/maternal-child-health-topics/child-health
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*Original article online at https://jamanetwork.com/journals/jama/fullarticle/2786823