Changes in ‘point-a’ on ‘angle SNA’ in angle’s class ii div 1 malocclusion cases treated with maxillary first premolar extraction– A cephalometric study

Aim: The aim of this study was to examine the Change in sagittal position of point- A and Effect of change in point-A on SNA Angle in Angle’s class II division 1 malocclusion cases treated with maxillary first premolar extraction. Materials and Methods: Pre and post treatment lateral cephalograms were collected from those who treated by PEA with MBT prescription with extraction of maxillary first premolars. Lateral cephalograms was analysed using various cephalometric parameters. The total change in the position of point A was measured by superimposing the pretreatment and post treatment lateral cephalograms on the sella-nasion (SN) line at the sella. Treatment changes in sagittal position of point A and SNA angle were calculated on pre-treatment and post-treatment lateral cephalograms which was analysed using Wilcoxon paired “t” test. Results: Point A has moved saggitally by 2.80mm backward and there is a decrease in the SNA angle by 0.520. Although VT-Point A shows significant change, its effect on Angle SNA is statistically nonsignificant. Conclusion: This study concluded that retroclination of maxillary incisors accompanied by backward movement of incisor root apex caused posterior movement of point A. However, this posterior movement doesn’t significantly affect the SNA Angle. Clinical significance: The present study is taken to evaluate the change in sagittal position of point A and its influence on SNA angle in class II div 1 malocclusion patients treated with maxillary first premolar extraction which will help us to assess the effective outcome in treating classII div1 cases.