What this site is for
This is patient education about the chin, published by Chongqing West District Hospital, a tertiary general hospital in Jiulongpo District, Chongqing. It is an area guide rather than a procedure page: it answers which of several structures is producing your complaint, which options address that structure, and how to choose between them. The operations and the injectables themselves are described on the guides this site links to, and repeating them here would help nobody.
The distinction the site is built on
Bone, bite and the soft tissue pad are three separate findings that produce the same complaint and are treated by means that have nothing in common. Almost everyone arrives with the three merged into one sentence, and naming the right one is most of the decision. A chin that sits back is therefore not automatically a bone problem, and a plan aimed at the wrong structure produces no visible change at all.
What it deliberately does not do
It does not name products or brands, quote prices or dosages, or promise a result. It does not present an injectable as a way of changing a bite or lengthening the face, because it does neither, and it does not describe a bone operation as reversible, because it is not. It does not describe surgical technique in detail and it does not tell you which route to choose: that follows from an examination, and a website cannot perform one.
The limits of a website
Nothing here can tell you how much of your own chin is bone and how much is soft tissue, whether your bite is contributing, or how much of the area is occupied by the nerve. Those answers come from someone measuring the chin against the lower lip and checking the occlusion, which takes minutes in person and cannot be taken from a photograph. Use this site to arrive at an assessment with better questions, and treat any answer you receive here as general information rather than as advice about you.