GET Prescription: Upper
U1, U2: .020″x.028″ slot
U1: 12°T, 5°A / U2: 8°T, 9°A
Normally, the problem with upper incisors is a lack of torque at the end of treatment. This is due to the play between the archwire and slot. In some prescriptions, an extra-torque series of brackets are available. With the GET prescription, it is preferred to decrease the size of the slot and maintain normal torque values. This has two advantages:
The play of a .019″x.025″ wire in a .022″x.028″ slot is 8,7°, which means in real life it is more, taking into consideration side-effects in the production process.
The play of the same .019″x.025″, wire in a .020″x.028″ slot is 2,8°.
U3: .022″x.028″ slot
U3: 0°T, 11°A
We have chosen the original straight wire with 11 degrees mesial tip, to allow for an increased arch length in the upper arch and 0 degrees torque to avoid too steep of canine guidance, which can lead to an immediate increase of Bennett movement.
U4, U5: .022″x.028″ slot
U4/5: -10°T, 4°A
We have chosen to add very little extra lingual crown torque (-10 degrees). We do not want to have upper premolars with a marked lingual inclination as an “open” position is better from a gnathological standpoint. However, 3 degrees extra negative torque are needed to compensate for side-effects of levelling, which tends to flare out premolars.
U6, U7: .022″x.028″ slot
U6: -20°T, 10°OF / U7: -25°T, 6°OF
We have reduced the value of the distal rotation to the original straight wire value (U6) and even less (U7) than that. This is to avoid that the disto-vestibular cusp of the upper second molar to project lingually, which is a major source of pre-contacts. We have also chosen to increase the lingual crown torque to reduce the tendency of pre-contacts due to hanging palatal cusps of upper molars (especially second molars).