Biprotrusive patients tend, on average, to demonstrate a decreased nasonabial angle 87, 0 ± 8, 240 and retrusive mandible78, 6 ± 3, 4 (0).. After treatment, mean PAR (W) indexwas 2, 9 ± 2, 94, reduction of 23, 0 ± 11, 67 equal to 87, 2 ± 12, 29%.