Assessment of four cephalometric measurements utilized in evaluation of the mandibular position

ABSTRACT

This study was conducted to assess and correlate four cephalometric measurements utilized in evaluating the mandibular position in the anteroposterior direction. The four measurements used were, the SNB angel, Downs facial angle, Bjork's facial angle, and modification of Koski's ratio. Lateral cephalometric radiographs of forty seven adults [20 males and 27 females] with age ranged from 18-20 years were selected for this purpose. All had accepted normal occlusions, normal skeletal relationship and balanced profiles. Statistical analyses were performed to assess these four measurements. The results revealed no significant difference between the norms of males and females in the four measurements. Downs and Bjork's facial angles presented more sysmmetrical normal distribution than SNB angle and Kosk's ratio. A low and non significant correlation was found between Downs and Bjork's facial angles. Therefore, their conjunctive use would be recommended. Finally, a high and significant correlation was found between Bjork's facial angle and SNB angle. Accordingly these two measurements could be interchangeable