Unequal Smiles: Socioeconomic and Spatial Inequalities in Children’s Oral Health in Northwestern China

INTRODUCTION AND AIMS: Children's oral health inequalities reflect more than differences in disease burden. They reveal how family disadvantage, limited service awareness, uneven dental provision, and geographic barriers jointly shape access to care. These inequalities may be especially pronounced in less developed regions, where socioeconomic and spatial disadvantages often overlap. Although previous studies have linked children's oral health to household background, oral health behaviors, and dental service use, few have examined parental perceptions, treatment completion, and spatial accessibility within one framework. Using Lanzhou in northwestern China as a case study, this study examines children's oral health burden, behaviors, service utilization, parental perceptions, and their socioeconomic and spatial determinants. METHODS: Using caregiver-reported data from 602 structured questionnaires, the study applied descriptive statistics, non-parametric tests, correlation analysis, regression models, random forest analysis, structural equation modeling, and spatial statistics. RESULTS: A substantial caries burden was observed, with 79.9% of children showing visible lesions. Higher burden was found among low-income and multi-child families. Dental service use showed clear inequality: younger children tended to seek care only when symptomatic, while urban core residents had higher utilization. Oral health behaviors were socially patterned, with higher-SES families showing better hygiene but higher sugar intake. Parental awareness of dental services was generally low, although demand for school-based prevention was high. Spatial analysis showed clustering of caries burden and service use, concentrated in disadvantaged areas. CONCLUSION: Children's oral health inequality in northwestern China is driven not only by family socioeconomic conditions, but also by disparities in service awareness, healthcare accessibility, and place-based factors. CLINICAL RELEVANCE: Improving parental awareness of pediatric dental services, strengthening school-based preventive programs, and reducing spatial disparities in healthcare access may contribute to narrowing inequalities in children's oral health.