Closing diastemas with aligners has a trap that shows up almost every time at the same point: once the incisors start retracting, the torque gets lost. The result is a retrusion that closes the space but leaves the incisors tipped palatally, with everything that means for aesthetics and long-term stability.<\/p>\n
Avoiding it doesn’t take extraordinary resources. It takes a sequence where torque is worked before retrusion starts, not during it and not after.<\/p>\n
Before any anterior tooth moves, the posterior segments have to be fixed.<\/p>\n
In cases with significant diastemas in both arches, the temptation is to start closing spaces from day one. But if the posterior segment isn’t consolidated as anchorage, the anterior closure drags the supporting teeth along with it, and controlling torque becomes close to impossible.<\/p>\n
What actually happens is that the posterior segments stay immovable while the arch is levelled at premolar and canine level, proclining the incisors at the same time. That initial proclination is what generates the torque overcorrection that will compensate for the loss that happens during the later retrusion.<\/p>\n
Torque overcorrection isn’t a cosmetic detail, it’s a biomechanical condition.<\/p>\n
When the incisors are proclined in a controlled way before retrusion starts, the system builds up an excess of labial torque that acts as a reserve. Retracting afterwards spends that reserve progressively, and the final torque lands in the right range.<\/p>\n
Try to do both at once, retract and hold torque at the same time, and the aligner can’t express both movements with the same efficiency. One of them gives way. It’s almost always the torque.<\/p>\n
A common mistake is treating the upper and lower arches as if they were independent.<\/p>\n
In the lower arch the sequence is the same: define the premolar position first, then retract the canines, checking throughout that no interference appears between the two arches. If an occlusal interference shows up at any intermediate stage between upper and lower, correcting the torque gets significantly harder, because the system starts compensating instead of progressing.<\/p>\n
When it’s time to retract the incisors, there’s an instruction that needs to go explicitly to the technician.<\/p>\n
The priority isn’t translation or the speed of retrusion, it’s torque. Ask the CAD designer to apply a degree of root torque per aligner on each tooth, keeping the overjet throughout the movement. That combination, constant torque plus preserved overjet, is what lets you reach the end of treatment with the incisors in the right position without sacrificing root angulation during closure.<\/p>\n
The conclusion of this protocol is also its most important premise.<\/p>\n
There is no “torque correction phase” at the end of treatment. Torque is managed before closure even begins, protected during retrusion with precise instructions to the technician, and checked at every stage to confirm there’s no interference between arches. When that logic is applied from the start, the result is diastema closure with the incisors in the right position, with no refinements needed to recover what a poor sequence lost.<\/p>\n
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