Research on racial/ethnic inequities in oral health over the past 80 years: The role of racism

Aim: This study aims to (1) describe trends in explanations provided for racial/ethnic inequities in dental caries and periodontitis, and (2) explore the patterns of relatedness among explanations for these inequities.

Materials and methods: Highly cited publications based on studies indexed in the Scopus database were retrieved and assessed for eligibility. Explanations for racial/ethnic inequities were classified into eight different, but interrelated domains. We assessed trends and examined the relations among explanations using multiple correspondence analysis.

Results: A total of 200 articles among the most cited publications were selected. The proportion of studies invoking racism as an explanation for racial inequities in oral health increased from 0% to 14.3%, from 1937 to 2020. The proportions of individual socio-economic factors increased from 52.0% to 82.9%, and dental care from 28.0% to 62.9%. The remaining explanations were stable: psychological/behavioural processes (62.5%), biological factors (49.5%), contextual/area-level effects (24.0%) and immigrant paradox (4.0%). Multiple correspondence analysis revealed a smaller axial distance between racism and the following categories: studies from Brazil, recent publications and Blacks/Hispanics/mixed-race groups. Publications about immigrants were axially closer to the high-income countries category.

Conclusions: Our findings call on dental researchers to consider racism as a cause for existing racial/ethnic inequities in oral health.