What's this dent / hollow area? Would I benefit from a revision septorhinoplasty? (Photo)

Without knowing what your nose looked like before, both inside and out, and what was done at your prior surgery, I cannot give you definitive answers. You also do not say how long ago the rhinoplasty was. An in-person consultation and your prior records are needed. However it appears that the attachement of the cartilage to the nasal bone has been separated on the right, which is a deformity I have seen many times, both after trauma and after an unsatisfactory rhinoplasty. Sometimes that can be filled with a filler injection or fat graft, sometimes it is better to reattach the cartilage, or place a cartilage graft at surgery. I would be confident though that this problem will not correct itself.
It also looks like your nasal bones are shifted a little to your right and the cartilage curves back to your left. This would go along with the septum still being deviated. When the cartilage is curved before surgery, it has a tendency to curve again, even if the surgery straightened it. Sometimes there are non-surgical fixes for that.
If your surgeon is well trained and has experience and a good reputation, I would try to work with him/her on these problems. If you feel you have reached a dead end with your surgeon, then it is time for a second opinion from a board-certified plastic surgeon who has skill and experience with revision surgery.

In general, a dent or hollow feeling could potentially be caused by a variety of issues, including cartilage irregularities, scarring, or internal nasal collapse.

Regarding cartilage healing, cartilage does have the ability to repair itself to some extent, but the healing process can vary from person to person.

I would suggest an in person consultation to assess your nose and a potentiel revision which may be needed in your case.

Best of luck !

Though this would not improve your nasal breathing, if you are self-conscious about the indentation along the sidewall of your nose, depending on your examination, microdroplet Silikon-1000 injections maybe considered for permanently filling in this divot. I hope this helps! Sincerely, Dr Joseph