Should I get a gum graft before or after Invisalign treatment?

HI, thanks for sending your question. You will find that after Invisalign your teeth are much easier to maintain and keep clean and that your issues with the build up on your teeth can get reduced greatly. If the need of any gum grafting existed before the treatment, it should then be addressed after your Invisalign treatment. I am confident that you will be very happy with your ultimate outcome of Invisalign treatment. All the best.

Almost always, the answer is orthodontics first. No dentist can 100% predict or guarantee the gum position, thickness and tone around each tooth until tooth straightening has finished.
Particularly if a gum graft has been recommended due to recession (a tooth/ teeth looking longer), this may become slightly worse after orthodontics depending on the specific tooth movements needed. So it usually makes sense to do the graft once... rather than graft, straighten, and possibly have to graft again...
I'd recommend discussing with a dentist skilled in comprehensive care. Look for Kois, Spear or Pankey dentists who understand how all these things fit hand-in-hand.

Without any information on your case, it is impossible to give an answer. However, the person most qualified to determine whether a gingival (gum) graft is needed and when it should be done is a periodontist, a specialist in treating the gums and bones. Ask your orthodontist for a referral and they should work together to determine the best treatment for you.