Cheekbones. Is it possible to push the zygoma and arch back out?

We commonly augment cheekbones with fillers. The best are the thicker Hyaluronic acid fillers such as Voluma or Restylane Lift. The filer can be specifically placed in the areas that you desire to fill out and last from one to two years. For more permanent treatment, malar (cheek) implants can be used. In rare circumstances, we can even have 3-D generated custom cheek implants made if stock implants are not the right shape or size.

Hello and thank you for your question. Based on your
photograph, you are a great candidate for malar enhancement.  This can be
done in one of two ways.  Voluma is an injectable filler which can be
injected into the malar region as a temporary filler.  Malar implants can
be placed as a permanent way to gain volume in the cheek.  I always use
medpor implants with screw fixation.  Silicone malar implants tend to
have a high rate of malrotation over time.  The most important
aspect is to find a surgeon you are comfortable with. I recommend that you seek
consultation with a qualified board-certified plastic surgeon who can evaluate
you in person.
Best wishes and good luck.
Richard G. Reish, M.D.  FACS
Harvard-trained plastic surgeon

Voluma® or Restylane® Defyne are particularly good for enhancing and shaping the cheeks and mid face/temples. Since this procedure requires injection expertise and an artistic eye, please consult a board certified aesthetic dermatologist for a consultation.  

While it is possible to do a bony reversal, it would be necessary to put an interpostional grafts between the re-osteotomized anterior cheekbone osteotomies. This is because there has been most likely a wedge of bone removed to allow it to move inward. Just pushing the bone back out will leave a bone gap that needs to be filled along with the plate and screw fixation.