A year and a half after BBL, I have a dent on the side of my butt. This is after my revision. What can I do? (Photo)

Hello and Great Question.  I appreciate the time you are spending researching this procedure.  My name is Dr. Matthew J. Nykiel.  I am a Board Certified Plastic Surgeon, a Fellowship Trained Cosmetic Surgeon, and a Butt Augmentation Specialist.
I think your options depend on the reason this has happened:  1) Did some of the fat not take?  2) Is this more of a bony asymmetry difference that is being seen and simply needs more on one side? 3) Or is this from "tight" connections to the skin (similar to cellulite) that is not allowing for the volume expansion.  
I believe you have options, but the options depend on what is causing the problem:  1) More fat transfer 2) Medical Grade Filler 3) Loosening of the tight connective tissues causing the problem.  
I hope that helps!  Best of Luck!
Matthew J. Nykiel, MD#TopREALSELFDoctor#CoreREALSELFDoctorButt Augmentation SpecialistLiposuction SpecialistBoard Certified Plastic Surgeon

Thank you for the question and photos. Based on these limited view photos, I'm not sure which area you are referring to. It seems like you are slightly bent forward and what I see is a flat posterior buttock, a large roll of fat on the lateral lower buttock, and an over suctioned area at the buttock/thigh junction. An in person examination by a board certified plastic surgeon experienced in advanced body sculpting techniques would be needed to see what improvement can be achieved. If you trust your surgeon talk to him/her or seek second opinions. Good luck.

Sometimes a dent cannot be corrected to the extent that is desired by surgeon and patient alike.  There is a certain resistance to change in tissues that can be responsible.