# Caries and Socioeconomic Factors in Adults (19–60 Years Old): An Updated Systematic Review of Observational Studies

## TL;DR

This review shows that adult dental caries is strongly linked to socioeconomic factors like income and education, highlighting the need for policies that address social inequalities to improve oral health.

## Contribution

This updated systematic review provides new evidence on the life-course impact of socioeconomic factors on adult dental caries, building on previous reviews from 2012 and 2018.

## Key findings

- Lower income, education, and manual occupations are strongly associated with higher caries experience in adults.
- Recent studies using life-course approaches confirm that persistent socioeconomic disadvantage increases caries risk.
- Oral health inequalities are cumulative and reflect lifelong social and economic disparities.

## Abstract

Public health relevance—How does this work relate to a public health issue?
Dental caries in adults, 19–60 years old, is a major public health issue linked to social inequalities, disproportionately affecting vulnerable populations.This review synthesizes global evidence on how social determinants like income, education, and occupation contribute to these oral health disparities.

Dental caries in adults, 19–60 years old, is a major public health issue linked to social inequalities, disproportionately affecting vulnerable populations.

This review synthesizes global evidence on how social determinants like income, education, and occupation contribute to these oral health disparities.

Public health significance—Why is this work of significance to public health?
This work confirms that adults with lower socioeconomic status face higher disease risk and greater subsequent tooth loss from untreated caries.Oral health inequalities are not static but are shown to be the cumulative result of social and economic disadvantage experienced across the life course.

This work confirms that adults with lower socioeconomic status face higher disease risk and greater subsequent tooth loss from untreated caries.

Oral health inequalities are not static but are shown to be the cumulative result of social and economic disadvantage experienced across the life course.

Public health implications—What are the key implications or messages for practitioners, policy makers and/or researchers in public health?
Reducing oral health inequalities requires a policy shift from individual behavioral interventions to addressing upstream social and economic determinants.Effective strategies must integrate oral health into broader social policies and strengthen universal access to comprehensive preventive and restorative dental care.

Reducing oral health inequalities requires a policy shift from individual behavioral interventions to addressing upstream social and economic determinants.

Effective strategies must integrate oral health into broader social policies and strengthen universal access to comprehensive preventive and restorative dental care.

Dental caries remains a major global public health problem characterized by pronounced social inequalities. This study aimed to identify, critically appraise, and synthesize the most recent evidence on the relationship between socioeconomic indicators and dental caries among adults aged 19–60 years, providing an updated systematic review that builds upon our previous reviews from 2012 and 2018. Reported following the PRISMA 2020 guidelines, we conducted a systematic search of eight electronic databases for observational studies published between March 2017 and April 2024 (PROSPERO: CRD42017074434). Two independent reviewers performed study selection, data extraction, and risk of bias assessment using the Newcastle–Ottawa Scale. Due to substantial methodological heterogeneity across the 22 included studies, a narrative synthesis was undertaken. The findings demonstrated a strong inverse association between socioeconomic position and caries experience. Lower income, lower educational attainment, and unemployment or employment in manual/unskilled occupations were associated with a higher overall caries experience. Advanced analytical approaches in recent studies, including life-course, reinforced that education and income are key contributors of these oral health inequalities, with persistent social disadvantage conferring the greatest risk. In conclusion, dental caries in adults aged 19–60 years is a social condition reflecting the cumulative effects of socioeconomic inequality across the life course. Addressing adult dental caries requires integrated approaches that combine clinical prevention with social and public policies aimed at reducing structural inequalities.