Comparative Study of the Prevalence of Occlusal Anomalies in Down Syndrome Children and Their Siblings.

Aims: The aim of this study was to characterize occlusal anomalies in a Portuguese population with Down Syndrome (DS) and to compare its distribution with that of their siblings. Study Design: A sibling-matched, population-based and cross-sectional survey was performed. Methodology: This study involved 132 children with DS and 84 of their siblings, aged 2 to 26 years. Data were gathered through the use of a complete questionnaire and clinical observation. Data analysis was performed by using SPSS® v.20.0 and any p-value <.05 was considered significant. Results: Seventy six percent of the DS children and 72% of their siblings showed class I of Angle. There were no statistically significant differences between both groups regarding class I (P=.60). Only 4% of the DS children presented class II versus 22% of the siblings (P=.001). Twenty percent of the DS children and 6% of the siblings presented class III (P=.008). The DS group presented occlusal anomalies more frequently, especially posterior crossbite (P<.001), anterior open bite (P=.005) and anterior crossbite (P=.001). Deep overbite was only found in the siblings group (P=.001). Conclusions: The results of this study suggest that children with Down syndrome have more occlusal anomalies than general population.