The existance of the relationships between cranial base flexure and prognathizm had been demonstrated by several authors. Present study reevaluates these associations by the use of a cephalometric analysis based on Natural Head Position, (NHP), and extracranial true HOR and VER reference lines. The study sample comprised NHP cephalograms of 106 dental students with an age range of 19-29 years. Results showed that the rotational orientation of the cranial base in the natural position of the head could be a determining factor for the degree of prognathism, while the cranial base flexion was found to be associated with the sagittal dimension of maxilla. Nevertheless, this effect did not result with an increase in maxillary prognathism.

Keywords: Prognatizm, Cranial Base Flexure, Natural Head Position, Prognathism