Patients with weak chins may have poor development of the entire jaw bone.  If they have a bite problem that they also wish corrected, they may benefit from a large operation in which the jaw bone is divided and slid forward. Patients with only a cosmetic concern, may be easily treated by a chin implant. Chin implants come in all shapes and sizes BUT they must rest on the bone.  Chin enhancement is only possible where there is bone underneath!  A chin implant will not push out the lower lip.  Feel the gutter behind your lower lip.  That's where the implant starts and even there it is thinnest. Extended implants are available that can enhance the jaw line, somewhat.  They do not replace a facelift.