jaw reduction removes support for your soft tissues allowing them to sag. It
takes away definition and makes one look older. Removing some fat (buccal
lipectomy) would provide more midface definition.
Cheekbone and jawbone reduction help make your face smaller and prettier
Based on your given photo, I would recommend you do cheek bone reduction and mandibular bone reduction ( Lower Jawbone reduction). These two procedures would help sweetening your face and make it more like V-shape. The incision for cheek bone reduction and mandibular bone reduction are located inside the mouth.
In order to make round face to a more oval or triangular shape, we do a combination of jaw reduction (reduction of angle to body of the mandible) to chin alteration (usually anterior projection), and change the cheeks (fuller by implant or injection). I recommend you to see a board certified plastic surgeon who specialize in this type of procedures.
Alex Kim, MD