Urbanization, mental health, and oral health inequalities in left-behind youth: a systematic review and meta-analysis.

PURPOSE OF REVIEW: This systematic review and meta-analysis evaluated mental and oral health outcomes among left-behind children (LBC) affected by urbanization-driven rural-urban labour migration. Although mental health impacts of parental migration are increasingly recognized, oral health outcomes remain underexplored. This review synthesizes available evidence, quantifies disparities, and identifies shared social and structural determinants.

RECENT FINDINGS: Thirty-three studies met inclusion criteria. Pooled analyses revealed significantly higher depressive symptoms among LBC compared to non-LBC peers [standardized mean difference (SMD) = 0.16, 95% confidence interval (CI): 0.03-0.29], with increased risk of elevated depressive symptoms [odds ratio (OR) = 1.36, 95% CI: 1.01-1.83]. LBC also experienced higher rates of permanent tooth caries (SMD = 0.15, 95% CI: 0.05-0.25) and were less likely to attend dental care in the past year (OR = 0.80, 95% CI: 0.67-0.94). Greater distress was observed in cases of shorter parental separation and when both parents had migrated. Factors such as caregiver education, quality of parent-child communication, and school climate consistently influenced outcomes across both mental and oral health domains.

SUMMARY: LBC experience a dual burden of psychological distress and unmet dental need, reflecting the effects of urbanization-related parental migration. These disparities are shaped by caregiving discontinuity, reduced access to preventive services, and socio-environmental stressors. Findings highlight the need for integrated responses, including caregiver training, school-based prevention, and equitable health entitlements. Addressing shared determinants across mental and oral health domains offers a feasible path toward improved outcomes and greater equity.

TRIAL REGISTRATION: PROSPERO ID: CRD420251152265.