Medscape, LLC is pleased to provide online continuing medical education (CME) for this journal article, allowing clinicians the opportunity to earn CME credit.

This activity has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education through the joint sponsorship of Medscape, LLC and Preventing Chronic Disease. Medscape, LLC is accredited by the ACCME to provide continuing medical education for physicians.

Medscape, LLC designates this Journal-based CME activity for a maximum of 1 AMA PRA Category 1 Credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

All other clinicians completing this activity will be issued a certificate of participation. To participate in this journal CME activity: (1) review the learning objectives and author disclosures; (2) study the education content; (3) take the post-test with a 75% minimum passing score and complete the evaluation at www.medscape.org/journal/pcd; (4) view/print certificate.

Release date: August 27, 2015; Expiration date: August 27, 2016

Despite marked improvements in the oral health of children and youth in the United States over the past decades, dental caries remains one of the most common chronic childhood diseases (1). By age 17, almost 70% of adolescents have experienced caries (2) and most (90%) caries in permanent teeth occurs in the pits and fissures (3). Dental caries disproportionately affect low-income children — 66% of adolescents living in poverty have experienced caries compared with 54% of children living in families with incomes greater than 200% of the federal poverty level (2). Although US children living in poverty are at higher risk for caries, only 1 in 4 has had at least 1 dental sealant (4).

Sealants are effective in preventing and controlling dental caries in the pits and fissures of permanent teeth (1). A recently published Cochrane review found that sealants reduced caries by 81% at 2-year follow-up (5). Another review found that placing sealants on noncavitated lesions reduced the progression of caries by 70% up to 5 years after placement (6). Increasing sealant prevalence among children at risk for caries is a national health objective (7). Both the Centers for Medicare and Medicaid Services (8) and the National Quality Forum (9) have endorsed performance measures related to increased sealant prevalence among Medicaid-enrolled and privately insured children, respectively, who are at risk for caries.

Factors associated with a child’s not having sealants include ability to pay for dental care (ie, low family income) (4); not having dental or health insurance (4); sociodemographic variables, including having parents who did not graduate high school (4); being of minority race/ethnicity (4); and low health literacy and low oral health literacy (10). A recent analysis found that parents’ functional health literacy and English being spoken at home were strong predictors of sealant prevalence among California school children (10). The RAND Health Insurance Experiment (HIE) also found that health literacy (ie, parents’ knowledge of the medical care system) predicted use of dental health services among children (11). Studies further suggest that one of the strongest predictors of medical and oral health literacy is educational attainment (12,13). Knowledge of the preventive benefits of sealants is also almost 5 times higher among people with more than a high school education compared with those without a high school education (34% vs 7%) (14).

Studies also indicate that factors affecting ability to pay for services may modify the effect of education on use of dental health services, although the direction of the effect varies by study. An earlier analysis of National Health Interview Survey (NHIS) data found that higher income predicted having a sealant only among children of parents who had a high school education or more (15). This analysis, however, was conducted in 1989 and reported that sealant prevalence among children aged 6 to 17 years was 16% (15), about half the current prevalence of 31% (4). Another early analysis from the RAND HIE found, however, that the presence of enabling resources (ie, removal of cost sharing from dental insurance plans) among less educated people resulted in more fillings and less untreated decay (16).

The predictive power of these factors largely can be explained in the context of Andersen and Aday’s predisposing, enabling, and need (PEN) model of health services’ use (17,18). According to the PEN model, health care utilization is a function of 3 factors: 1) demographic and social characteristics that influence a person’s attitudes and valuation of health, which in turn predispose a person to use care; 2) location and availability of health care as well as personal resources that enable a person to access care; and 3) a person’s perceived need for care.

In this article, we examine the association between sealant prevalence and predisposing, enabling, and need variables. In light of the findings of the analysis of NHIS data, of special interest is whether the association between sealant prevalence and education, a predisposing variable, is still modified by income, an enabling resource. We hypothesize that predisposing variables will have higher predictive ability in the presence of sufficient enabling resources or alternatively that enabling resources will have higher predictive power among parents predisposed to use sealants.

Excluded children had less educated parents but lived in families with income levels similar to those of children included in this study (Table 1). Excluded children were also older, less likely to be non-Hispanic white, and more likely to be “other race/ethnicity.” Overall, among children aged 6 to 19 years in NHANES 2005–2010, including children excluded from our analysis (n = 7,916; data not shown), sealant prevalence was 32.9% (SE = 1.0%). Sealant prevalence did not differ between children included and excluded from our study (Table 1). Furthermore, the sample used in this analysis (n = 7,090) was comparable to the total number of children in the combined NHANES database (n = 8,275; data not shown).

Sealant prevalence was associated with all independent variables (Table 2). Sealant prevalence increased with level of parental education and family income. Sealant prevalence was also higher among older children, girls, and non-Hispanic white children compared with younger children, boys, and non-Hispanic black and Mexican American children. Children with private health insurance and those with a usual source of care also had higher sealant prevalence than did children with Medicaid/SCHIP, other government insurance, or no insurance and children without a usual source of medical care. Sealant prevalence also was higher among children in excellent to very good health compared with those in good or fair/poor health — the indicator used for future need for dental care in this analysis. Finally, compared with previous NHANES cycles, sealant prevalence was higher in 2009–2010.

Before controlling for potential covariates, we found that sealant prevalence differed only by parental education among the middle- and high-income groups (P values for lowest income group always exceeded .80; data not shown). Among the middle-income group (100%–200% of the FPL), the differences in sealant prevalence among children of parents who had more than a high school diploma (prevalence, 30%) or a high-school diploma (28%) compared with less than a high school diploma (22%) were 8 percentage points (P = .007) and 6 percentage points (P = .04), respectively. Among the highest income group (>200% of the FPL), the differences in sealant prevalence between children of parents who had more than a high school diploma (40%) or graduated high school (35%) compared with parents who were not high school graduates (25%) were 15 percentage points (P < .001) and 10 percentage points (P = .04), respectively.

This study used Andersen and Aday’s PEN model of health care utilization (17) to examine whether the association between sealant prevalence in children and the predisposing factor, parental education, varied by the enabling factor of family income, controlling for other predisposing, enabling, and need variables. Andersen’s model has been expanded since its initial conception to include additional variables (18) but, as suggested by the model’s authors, we used the original model because of data availability and its suitability to our research question (17). We found that, although sealant prevalence did not vary by level of parental education among children from low-income families, having a parent who was educated beyond high school (vs a parent who did not graduate high school) was associated with an almost 50% increase in sealant prevalence among children from high-income families (26% among <high school diploma vs 38% among >high school diploma).

To the extent that education and income are good measures of predisposing and enabling variables, respectively, our findings suggest that parents predisposed to having their child receive sealants require sufficient enabling resources or that parents with sufficient enabling resources must be predisposed to having their child receive sealants. We classified education as a predisposing factor because of its strong association with health literacy (12,13), which in turn predicts higher sealant prevalence (10). This classification is also consistent with Andersen and Aday’s identification of education as a predisposing factor in their PEN model (17).

Although we had 3 measures of enabling resources (income, health insurance, and usual source of health care), we used income as the primary proxy for enabling resources. We did so because the other 2 items measured enabling resources for medical as opposed to dental care. Analyses conducted during the 2005 to 2010 timeframe of this study suggest that approximately one-fifth of children with health insurance do not have dental insurance — approximately 94% of US children had health insurance (23) while only approximately 75% had dental insurance (24). In addition, health insurance may be more enabling for health care than dental insurance is for dental care — dental insurance has higher copays and lower annual limits than medical insurance and, as a result, approximately 40% of dental expenditures are paid out-of-pocket (25).

The finding that increased education was not associated with increased sealant prevalence among children from low-income families is noteworthy because these children are eligible to receive Medicaid dental benefits in all states (26). Medicaid dental coverage, however, may be less enabling than private dental insurance. Dentists may be less likely to participate in Medicaid for reasons such as lower reimbursement rates. In 2013, for example, the average Medicaid fee-for-service reimbursement for children’s dental services was less than half (48.8%) that of commercial dental insurance charges (26).

Our findings deviated from the PEN model in that the variable we included to reflect future need for care (poor perceived child’s health status) was associated with lower sealant prevalence. These results are similar to those from another study of factors influencing receipt of preventive medical and dental care where children with self-reported poor health status were less likely to have received preventive pediatric health and dental care (27). Poor general health may not only indicate higher caries risk but also poorer access to care due to limitations in mobility or financial resources. Children in poor health may use more treatment or acute care services at the expense of needed preventive services (27).

Our study has limitations. Because this analysis used cross-sectional data, our findings can be interpreted only as an association rather than a causal factor of children’s having sealants. In addition, family income, parental education, insurance, and health status were self-reported with no objective measures to confirm validity. A final limitation was the change in the NHANES examiner type from health technologists to dental hygienists between 2005–2008 and 2009–2010. However, the clinical assessment criteria did not change nor did the reference examiner change and any potential differences because of the change in examiner type should be partially captured by the survey year variable.

Our findings suggest that the impact of higher parental education on a child’s having sealants is greater in the presence of higher family income and that the impact of higher family income on a child’s having sealants is greater in the presence of higher parental education. Interpreting our findings in the context of oral health care for children in the United States suggests that sealant prevalence could increase. Recent health care reforms will probably enable more families to obtain preventive dental services (including sealants) for their children through increased access to dental insurance and increased supply of dental providers (4). Andersen and Aday argued that addressing enabling variables would be the most effective strategy to achieve equitable access to health care, as these resources could be altered with changes in government policy (17). Predisposing factors such as education, however, are considered less mutable in the short run. If education is indeed capturing the influence of health literacy, then it may be possible to alter a parent’s predisposition toward sealants with health literacy campaigns. The renewed focus on the importance of oral health literacy could in a short time result in more families being aware of the importance of good oral health and the preventive benefits of dental sealants. Health and oral health literacy are a focus of interest at the national level, as demonstrated in the recommendations from a recent Institute of Medicine workshop (28), objectives in Healthy People 2020 (7), and the Health and Human Services National Action Plan to Improve Health Literacy, which includes an oral health component (29).