Most rotations greater than 30 degrees are considered challenging movements. The degree of rotation correction may depend on a number of factors:
1. Shape of the tooth. Some teeth will not have surfaces that allow the aligner to adequately "grip" them for rotation.
2. Type of attachment used.
3. Length of the root.
4. Axis of rotation.
5. Amount of space available for rotation.
6. Order of movement.
Sometimes, sections of fixed braces, buttons, and/or elastics are used to allow rotational correction using Invisalign.
There are no hard and fast rules about Invisalign and orthodontics in general. Each specific treatment plan has to be tailored to the individual situation by an experienced Invisalign orthodontist or dentist. Best of luck!