Deep bite correction with a tip back
If we utilize the tip back bend for the correction of a deep bite, it can clearly be seen that when the short segment of the bend is inserted in the molar tube, the large segment directs itself to the apical portion of the anterior zone(before being inserted in the slots of the braces of the incisors). This way we know that an intrusive force will be produced on the anterior zone and an extrusive force in the posterior zone. Another consideration that we have to mind with the placement of bends is that the short segment of the arch wire is going to represent the anchorage side, and the long segment of wire the side of no anchorage, this is due to the fact that Moment at the molar level (short part of the bend) is greater than the one that is being produced at the incisor level, making the molar much more resistant to movement.
When the arch wire is activated by placing it in the slots of the incisor braces, two moments are going to be produced, one at molar level and another at the incisor level, provoking a differential torque on both teeth.
A mesial root movement and a distal crown movement is going to be produced in the molars, meanwhile since the intrusive force passes buccal to the center of resistance of the incisors, the moment is going to be lower, taking the incisor to a more buccal position.
Once tip and torque have expressed themselves completely at incisor and molar levels, the slight extrusion that is produced with the mesial angulation of the molar is going to aid in the correction of the deep bite together with the intrusion of the anterior segment.
In both cases the moment that is produced in the anterior sector, product of the intrusive force, projects the incisal edges of the incisors in a buccal manner increasing the arch length and correcting the deep overbite.