MSC - Page 28

ORTHODONTICS Table 1: Pre and post treatment cephalometric changes of patients treated by R-appliance Before Treatment After Treatment Difference Landmark P Value Mean SD Mean SD Mean SD SNA ° 80 2.6 79.8 2.9 -0.3 1.8 0.5 SNB ° 72.8 2.2 76 1.8 3.3 1.5 0.001* ANB ° 7.3 2 4.1 1.8 -3.2 1.6 0.001* Y-axis ° 73.5 3.2 72.7 3 -0.8 1.8 0.07 GoGn-SN ° 39.2 4.4 38.6 5 0.6 2.7 0.3 Gonial Angle ° 133 5.8 132 5.5 -0.8 2.6 0.2 Inclination Angle ° 84.5 2.6 85.7 3.8 1.1 4.9 0.3 U1-SN ° 102 7 96 6.5 -6.1 5.6 0.001* IMPA ° 101 7.2 98 9.7 -3 5.4 0.02* Interincisal Angle ° 117.6 9.5 127.8 12 10 8 0.001* U1-Na (mm) 4 3 2.1 2.6 -1.8 3.4 0.02* L1-NB (mm) 4.6 1 4.5 1.4 -0.1 0.4 0.6 Occlusal to SN ° 23.9 3.5 23.6 3.8 -0.2 3.3 0.7 Jarabak (%) 59.2 3.4 61 3.5 1.7 2.5 0.007* * P value was set at 0.05 Discussion: Class II division I malocclusion presents either with a prognathic maxilla and a normal mandible, or a normal maxilla and a retrognathic mandible, or even a combination of both. In this study all the case ́