Introduction. Down syndrome occurring in Poland with a frequency of 1: 588 live births and is associated with the occurrence of characteristic features of body and various degrees of mental retardation, as well as the appearance of congenital defects of selected internal organs. Typical features also apply to the structure of the facial part of the skull, including reduction of the length of the anterior cranial base or hypoplasia of the middle part of the face. Aim. Comparison of cephalometric analysis results between children with Down syndrome and without this syndrome, in particular identification of specific cephalometric parameters that tend to increase or decrease in value. Material and methods. In the study was performed 15 cephalometric analysis of children with Down syndrome, in the age group from 8 to 14 years of age, and 15 analysis of children without this syndrome, at an adequate age. The obtained results were compared between groups and referred to the Segner and Hasund norms, then subjected to statistical analysis. Results. The angles SNA, SNB, ANB, NSBa, NL‑NSL, ML‑NSL, ML‑NL, 1+: NA, 1: NB and the interincisal angle are repeatedly deviated. Deviations in the SNA, ANB, NSBa, 1+: 1-, 1+: NA angles are statistically significant. The values ​​of the anterior cranial base length and the maxilla length in the group of Down syndrome children are significantly lower compared to the control group. Conclusions. The noticed deviations of individual parameters become a stimulus to consider the purpose of developing separate cephalometric norms dedicated to Down syndrome children, which would be optimal for them.

Key words: Down syndrome, trisomy 21, cephalometric analysis..