Effect of premolar extraction on mandibular rotation

Various types of appliances have been tried by the Orthodontists for fixed orthodontic treatment. Irrespective appliance used main goal retraction anterior teeth in extraction cases is to keep vertical dimension stable so as not allow downward and backward rotation mandible. The aim this study was compare changes mandibular following treatment on subjects who undergone all first premolars. Pre post lateral cephalogram 25 were taken (13 females 12 males), aged 18-25 years tracings done using Nemoceph software. Parameters assessed facial height (anterior posterior), plane angle (FMA & SN-GoGn), Jaraback ratio. Student t-test make statistical comparison. Mean difference SN-GoGn(0.15 ±0.07), FMA(0.23 ±0.52), Anterior height(0.18±0.01) posterior height(0.45±0.01) ratio(0.47±0.32) did show statistically significant between pre Mandibular alter during When adequate mechanics followed desirable outcome with insignificant alteration can be achieved.