Lateral rotation, the watermelon seed effect, is caused by tight contacts. Run 0.1mm IPR between the anterior contacts at the start of treatment rather than waiting for the problem to appear.

What to do

1. At the start of treatment, proactively run 0.1mm IPR between all anterior contacts, even where no IPR is planned in the treatment plan.
2. Add attachments to the lateral incisors where you can. Lingual attachments are preferable for aesthetically minded patients.
3. At each review, recheck the anterior contacts with floss and run further 0.1mm IPR if they have tightened again.

Still need help

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