Bilateral Premolar Extraction vs Distalization: A Randomised Clinical Trial

Rationale: Class II Division 1 malocclusion is characterized by upper anterior teeth protrusion resulting in upper lip protrusion and convex facial profile, which are considered esthetically unfavorable. Treatment of class II malocclusion due to maxillary protrusion can be done with bilateral maxillary first premolar extraction followed by en-masse retraction of upper anterior teeth using mini implants placed between maxillary 2nd premolar \& 1st molar. Treatment of class II malocclusion due to maxillary protrusion without premolar extraction frequently requires distalization of maxillary molars into Class I molar relation by means of extra-oral or intraoral forces. Absolute skeletal anchorage, available 24 hours a day is an alternative method for molar distalization. Zygomatic miniplates fixed at a distance from the root apices, allows distalization of entire dentition as there is no interference between the fixation device and roots of the teeth. Aims and Objectives: To evaluate dental, skeletal \& soft tissue changes achieved with maxillary premolar extraction vs full arch distalization. Method of study: Patients will be allocated randomly to 2 groups-G1 and G2. Patients in G1 will undergo bilateral maxillary 1st premolar extraction before bonding followed by leveling \& alignment. Maxillary arch will be stabilized with the help of 0.019"×0.025" stainless steel wire. Hooks will be soldered on archwire used for stabilizing dentition. Mini implants will be placed under local anaesthesia between maxillary 2nd premolar \& 1st molar. Ni-Ti closed coil spring will be used to apply a force for en masse retraction of maxillary anterior teeth . In G2, treatment will be initiated by bonding 0.022" slot MBT preadjusted edgewise appliance. Maxillary arch will be stabilized with the help of 0.019"×0.025" stainless steel wire. Zygomatic miniplates will be placed bilaterally. Hooks will be soldered on archwire used for stabilizing dentition. Ni-Ti closed coil spring will be