Aligners and Bowing Effect

Bowing in English translates to curvature and in orthodontics this term indicates the curvature of the occlusal plane.

As described in Richard McLoughlin's text, the bowing effect typically occurs when trying to close spaces in the arch using elastic chains applied to super-elastic wires. Therefore, space closure in multibracket devices should be postponed until the end of the leveling and alignment phases when using rigid arches.

When using dental aligners, occlusal plane curvature is not a complication unique to extraction treatment.

The bowing effect is always around the corner whenever aligners are applied to close excess spaces in the arch, sometimes even small ones.

In 2018 when I treated this case in the picture I thought that the curvature of the occlusal plane was a complication exclusive to extraction treatments.

I was wrong and finding the solution to the problem required first identifying the dynamics responsible for it.

Why can this happen so frequently?

Dental aligners enclose the teeth within a totally elastic force system in which the programming software often tends to overlap the phases of leveling, alignment and closing spaces. Despite the different types of plastic materials, the rigidity offered by a steel arch is not achievable.

How to solve this complication?

TADS?

Power arms?

No, all it needs is proper digital orthodontic biomechanics programming.

Correct programming can manage the problem once it has arisen and, if applied from the early stages of treatment, prevent it.