Botox jaw reduction only works if the muscle is enlarged. Botox is injected into the it and weakening it so it gradually becomes smaller through atrophy over the span of a few months. However results are not seen generally for 1 to 3 months and peak results at around 3 to 9 months. The nice thing about this is there is no down time and the improvement is gradual so many people you interact with are much less likely to notice it. Again this only works if you have an overly enlarged jaw muscle, if not you're just throwing away money because it's not going to do anything to your bone.
“One popular new plastic surgery technique is called lip grafting, or "fat recycling" wherein fat cells are removed from one part of your body that is too large, such as your buttocks, and injected into your lips; people will then be literally kissing ass.”