RESUMO
BACKGROUND: Previous studies have shown a high prevalence of malocclusion in people with Down syndrome (DS) compared to individuals without DS, but no systematic review to summarize the evidence on this topic has been performed thus far. AIM: To evaluate whether children/adolescents with DS are more affected by malocclusion than those without DS. DESIGN: A search was performed in seven electronic databases. The quality of the included studies was assessed using the Newcastle-Ottawa Scale. The strength of the evidence from the selected studies was evaluated by the Grading of Recommendations Assessment, Development and Evaluation system. RESULTS: Eleven publications were included in the systematic review and eight were meta-analysed. The meta-analysis showed that malocclusion was more prevalent in children/adolescents with DS for Angle Class III (risk difference [RD] = 0.40; confidence interval [CI] = 0.33, 0.46), posterior crossbite (risk ratio [RR] = 3.09; CI = 2.02, 4.73), anterior crossbite (RR = 2.18; CI = 1.41, 3.39), and anterior open bite (RD = 0.21; CI = 0.06, 0.36). CONCLUSION: The occurrence of malocclusion was higher in children/adolescents with DS compared to individuals without the syndrome. The strength of the evidence of the studies analysed, however, was considered moderate and low.