Background <p>Although oral diseases are among the most prevalent chronic conditions affecting children and adolescents globally, access to preventive and treatment services remains uneven. These disparities are particularly pronounced among Indigenous populations and reflect long-standing structural and social inequities. This study examined the prevalence of, and ethnic inequalities in, refraining from dental care and inadequate toothbrushing frequency among Indigenous and non-Indigenous children and adolescents in Ecuador.</p> Methods <p>A cross-sectional study was conducted using a nationally representative data from the ENSANUT 2018 demographic survey. Two preventive oral health outcomes were included: refraining from dental care in the previous 12 months and inadequate toothbrushing frequency (&lt; 2 times/day). Ethnicity was self-reported and categorized as Indigenous or non-Indigenous (Afro-Ecuadorian, Mestizo, White, and Montubio). Survey weighted prevalence and absolute risk differences between ethnic groups were estimated to assess inequalities in the outcomes, with adjustment for sex, place of residence and region, and stratified by age group.</p> Results <p>Refraining from dental care was more prevalent among Indigenous than non-Indigenous children (50.6% vs. 37.3%), corresponding to an adjusted absolute risk difference of 9.2% points (95% CI: 4.4 ̶ 13.9). Inadequate toothbrushing was consistently higher among Indigenous children and adolescents, with an adjusted absolute difference of 12.8; 95% CI: (9.8 ̶ 15.9) and 11; 95% CI: (7.8 ̶ 14.3) percentage points, respectively.</p> Conclusions <p>Substantial ethnic inequities in access to dental care services and preventive oral health behaviour persist among children and adolescents in Ecuador. These findings underscore the need for equity-oriented and culturally appropriate oral health policies targeting Indigenous populations.</p>