Why this site begins with a question rather than a treatment
A general guide to wrinkle-relaxing injections describes what the treatment is and whether to have it. That is the parent site in this cluster, and it is not repeated here. This site exists for the question that has to be answered before any of it applies: is the width of this lower face the muscle at all? Three different layers produce a similar appearance from the front, and only one of them answers to an injection.
Why reversibility is treated as the main subject
The effect of this treatment fades and the muscle returns to its previous size. That single fact decides most of the rest: whether the treatment is worth starting, why the first plan is conservative, why a review is scheduled rather than a course, and why a patient who needs an appearance that does not change is looking at something else. A site that described only the change and not the return would be describing half a treatment.
How it is reviewed
The content is medically reviewed by Ke He, MD, head of skin and laser aesthetics at Chongqing West District Hospital, and the review date appears on every article. The site names no product and no brand, describes the medicine only by its class, quotes no dosage and no price, promises no outcome, and states plainly that the change reverses and that the width returns.
What this site cannot do
It cannot tell you how much of the width in your own face is muscle, how your two sides compare, or whether your clenching happens by day or in sleep. Those come from an examination and from a history. Read this site to arrive at that appointment able to ask which layer is responsible, how much of the width the muscle explains, how the two sides differ, when the effect would fade, and what would be done if the response were not the expected one.