UPPER INCISORS
Tip, angulation, and in-out
Centrals have +17° torque and +4° angulation.
Laterals have +10° torque and +8° angulation.
Upper laterals have reduced in-out compared with the research figures (please see below and the web page ‘In-out reconsidered’ ).
The -10° torque option for upper laterals
When a case has instanding upper lateral incisors, it is often helpful to invert the bracket, giving -10° torque instead of +10°. The displaced lateral incisor carries the normal bracket, but it is rotated through 180°. The angulation (tip) stays the same at 8° but the torque becomes -10°. Switching sides is not correct. The left bracket must go on to the left incisor and the right bracket on to the right incisor. Inverting the bracket in this way applies effective labial root torque at the rectangular wire stage, for easy root correction.
It is normally better to achieve correct incisor and canine torque from bracket versatility. The alternative is wire bending, but it is difficult and time consuming to introduce the exact amount of torque needed into rectangular wire. Inverting the bracket is a more precise and easier way to achieve the same outcome. The authors recommended this in 1997 and included a published case in their second book ‘Orthodontic Management of the Dentition’ (p. 98–104) and a treatment sequence in their third book ‘Systemized Orthodontic Treatment Mechanics’ (p.43).
To reduce the need for wire bending in this way it is essential to use accurate brackets and to bond them correctly.
Reducing in-out for upper laterals
As discussed on our earlier web page ‘In-out reconsidered’, the upper lateral incisor brackets have reduced in-out compared with the research figures, because this gives better smile aesthetics.
Andrews’ research found that the upper lateral incisor inset was 0.55mm compared with the centrals. However, in many cases, this amount of inset does not give rise to an outcome that will please the patient. This is why our reduced inset on upper laterals has become best practice and is popular with patients.
Upper incisor brackets
Inverted upper lateral incisor brackets give -10° torque and +8° angulation in cases with in-standing laterals.
In cases with instanding upper lateral incisors it is often helpful if the bracket is inverted.
An occlusal view of a case, close to completion. It shows the slightly increased prominence of the upper lateral incisors, resulting from the reduced in-out on the brackets. This gives better smile aesthetics, which is much appreciated by patients.