By means of tensor analysis this cephalometric study was undertaken to compare the growth differences of the facial skull of untreated orthodontic patients. We investigated children with small cranial base angle (BaSN = 128-132 degrees) and another group with an angle greater than 132 degrees. In this cross-sectional study we compared the development of the skull from an age of 7 to 8 years to an age of 9 to 10 years. In contrast to patients with small cranial base angle those with flatter base showed an increased vertical growth. The growth of the midface and mandible tend toward a retrognathic face. Angle Cl.-I cases showed a proportional horizontal growth pattern in all regions of the face.