I had a sliding genioplasty, maximum projection 10mm, would like further projection. Can I get a 2nd SG for further projection?

You may be a candidate for a second sliding genioplasty. The plates and screws are removed and a second genioplasty is performed and further advancement can be achieved. Jaw surgery is not recommended since you have a normal bite.

Your situation is at this point fairly complex and I think it’s beyond giving a quality assessment based on pictures.
I suggest you rely on in person consultations exclusively.
This type of work is done by both plastic surgeons and oral surgeons.
I suggest consulting with oral surgeons or plastic surgeons who have cranial facial surgery background.
Best,
Mats Hagstrom, MD