My 12 yr old son, had partial removal of ingrown toenail, 6mth ago. condition come back again. to remove the toenail is it a better option?

Not usually: There are 2 different procedures. One is just cutting out the ingrown edge to allow it to heal. The second destroys part of the root so the ingrown edge doesn't return. If only the first was performed, it is possible for problems to return. If this happens, the permanent procedure is indicated , but only for the ingrown edge(s).

Depends: Did your son have a matrixectomy? Sometimes they can regrow but if didn't have matrixectomy i would suggest that be incorporates instead of removal of whole nail.

Removal.: After removal you can let the border grow out again (it sounds like this was already attempted, with recurrence of the problem), or your doctor can use a chemical to stop the nail from regrowing. The use of the chemical will cause the site to drain a little longer, but won't increase the pain of the procedure or recovery afterward. About 95% effective in my experience.