It is possible to build muscle on my outer thigh to diminish the dent without having fat grafting? (Photo)

The short answer is no, muscle tone will not change this irregularity that was from overly aggressive liposuction in the wrong area.  Fat grafting with subcision can help improve the contour.  Best, Dr. Emer.

Muscle building will make the entire muscle in that region bigger but it will not fill in the dent. Fat grafting would be necessary to fill this area in and should work fairly well. 

The depression that your photo demonstrates would be very amenable to improvement with fat grafting. Increasing muscle bulk cannot fill out a specific area; it will just make the whole thigh larger.

I think the dent will be able to be camouflaged with some fat grafting to the area.  I do not think building muscle will get rid of the dent.  Speak to your plastic surgeon about your concerns and go over your options.

Thank you for the photo and question and though a full exam is needed, if you are having lipo done, I would transfer some of the fat to the dentDr Corbin

First of all one will have to decide whether the root cause of depression is from muscle atrophy or loss or from localized loss of fat.It will be very difficult to decide that  without examining you.It will be almost impossible to correct the above depression just by exercise.Whatever is the cause,the simplest solution is fat grafting.May be one of these in future  we will master the technique of transplanting muscle stem cells to solve this kind of problem only if the cause is muscle loss!But for now best solution is fat grafting.