Most easiest movement during orthodontic treatment is:

The uncontrolled tipping in which the crown moves distally and the apex mesially; this is the easiest type of tooth movement to achieve from a clinical standpoint. In removable appliances, springs or screws cause uncontrolled tipping because there is only single force acting on the tooth, and there is no attachment on the tooth for an opposite moment. A similar type of movement is observed in the Begg technique in which the teeth move on round wires.