Children’s Dental Sealant Use and Caries Prevalence Affected by National Health Insurance Policy Change: Evidence from the Korean National Health and Nutrition Examination Survey (2007–2015)

Abstract

We evaluated the effect of the National Health Insurance (NHI) policy including dental sealant on changes in the prevalence of sealant and caries, and examined how NHI affected sealant utilization and untreated caries in children from diverse income groups in South Korea. We used a multivariate logistic regression analysis to explore the effects of three stages of dental sealant policy (pre-policy: 2007–2009, first post-policy: 2010–2012, and second post-policy: 2013–2015) on the prevalence of dental sealant and untreated caries. Participant data (N = 8161, aged 6–14 years) were derived from the Korea National Health and Nutrition Examination Survey (2007–2015). We also conducted subgroup analysis to determine the effects of the NHI policy on dental sealant and untreated caries by income level. Implementation of dental insurance coverage was associated with higher likelihood of using dental sealant (odds ratio (OR) = 1.39 (95% confidence interval (CI): 1.18–1.63) for the first period and OR = 1.58 (95% CI: 1.33–1.87) for the second period) and lower odds of having untreated caries (OR = 0.79 (95% CI: 0.64–0.98) for the first period and OR = 0.65 (95% CI: 0.51–0.83) for the second period) after controlling for covariates. Results revealed that there was a greater prevalence of dental sealant and a lower prevalence of untreated caries in both middle- and low-income households compared to high-income households. The higher prevalence of dental sealant and lower untreated caries after the policy implementation. Moreover, we demonstrated children from low-or middle-income households were more associated with increasing dental sealant use and a declining prevalence of caries.

Did the extended coverage policy contribute to alleviating socioeconomic inequality in untreated dental caries of both children and adolescents in South Korea?

“…After the coverage expansion of dental sealants, the prevalence of untreated dental caries decreased and that of having sealant treatment increased in both children and adolescents. This study also showed an overall increase in dental service usage after the coverage expansion [17]. A similar review on smoking inequality in youth after tobacco control policies concluded that [40] education and information communication led to widening inequalities, while the tobacco price policy reduced socioeconomic inequalities.…”

“…Based on the review of the effects of public health policies on health inequalities, Thomson et al [42] concluded that two types of oral health interventions had positive effects on inequalities: water fluoridation [43] and a national tooth brushing education campaign [44]. Another study pointed out that dental insurance is an important driver for dental service use, as tackling financial barriers mostly reduces unmet dental needs [17,45]. US studies to examine the effects of the Children's Health Insurance Program also reported an increase in sealant treatment, fluoride tablets, and dental visits and a decrease in untreated caries since 1997, especially in children from lower-income households who benefited from free or subsidized school lunch programs [46].…”

“…Accordingly, the proportion of children aged 6-14 years who received dental sealant increased encouragingly, from 28.7 to 34.9% [16]. A Korean study reported that after the policy implementation, dental sealant increased and untreated caries decreased, especially among lower SEP groups [17]. Many existing studies have suggested that equal access to dental treatment is essential to improve the dental status of all [18].…”

Did the extended coverage policy contribute to alleviating socioeconomic inequality in untreated dental caries of both children and adolescents in South Korea?

“…After the coverage expansion of dental sealants, the prevalence of untreated dental caries decreased and that of having sealant treatment increased in both children and adolescents. This study also showed an overall increase in dental service usage after the coverage expansion [17]. A similar review on smoking inequality in youth after tobacco control policies concluded that [38] education and information communication led to widening inequalities, while the tobacco price policy reduced socioeconomic inequalities.…”

“…Accordingly, the proportion of children aged 6-14 years who received dental sealant increased encouragingly, from 28.7-34.9% [16]. A Korean study reported that after the policy implementation, dental sealant increased and untreated caries decreased, especially among lower SEP groups [17]. Many existing studies have suggested that equal access to dental treatment is essential to improve the dental status of all [18].…”