When an engager is not lining up with the space created for the engager in the aligner, it can cause discomfort or pain when applying and removing the aligners, and can delay the movements of the affected teeth towards the final result indicated in the treatment setup. Another term used to describe this situation is to say that the engager is "not tracking".
Engagers not fitting in the aligner can be caused by any of the following:
- When a patient is non-compliant
- Tooth movements have not occurred due to insufficient pressure or lack of space (rotations, extrusions, intrusions, torquing, tipping, translating)
In this situation, you don't want to force the aligner into place over the misaligned engager - this can do more harm than good by moving the tooth in unwanted ways.
Try the following:
- Remove the engager that's not fitting in the aligner, and use the previous aligner as a template to place a new engager on that same tooth.
- Check for tight contacts that may be preventing movement and if you find any, follow instructions given for breaking tight contacts.
- Try backtracking with the previous aligner, the teeth may just need more time to make the needed movement.
- Though the engager will still apply pressure to the tooth and work towards completing that difficult movement, there may be a slight gap in the aligner because that tooth will be moving a little behind schedule. (In the meantime, Chewies may help close those gaps and help your patient feel more comfortable.)
- If the aligner fits everywhere else, remove the engager that isn't fitting into the aligner and continue with treatment. That particular tooth probably will not move as scheduled on the treatment plan, but the movement can be completed later with a refinement at the end of treatment using auxiliaries or dimples.
- If all else fails, remove the engagers from all of the teeth, take new upper and lower impressions, and request a case revision. This may delay treatment, but it will allow us to tweak the treatment plan for that particular tooth.