highly significantp =0.001
Thought the mean age of the Class I extraction group 18.81 years, the tooth size arch length discrepancy -2.33 mm and the proclination of lower incisor to NB of 9.5mm in the Class I extraction group was very highly significant ( p =0.001) ( Table 2 ) compared to the non extraction group with tooth size arch length discrepancy of 0.5mm and lower incisor to NB of 6.86mm.