I'm stressed because I have no chin,
 so I'm thinking of getting chin augmentation (lengthening), but
 
they say that if you contour it, the weight will sag.
 However, since chin advancement surgery involves removing the chin from the front, should I worry about sagging weight?
 I'm actually a bit slim, so I'm planning on not touching anything else (cheekbones/square jaw) and just
 getting a real chin augmentation.
 
Is there anyone who has had surgery to advance the chin?