What is the best way to get rid of my chin dimple? (photo)

Never ever inject there (or elsewhere in the face) fillers, silicone, etc; botox is neither the solution; the key for a successful treatment of literally anything begins with... understanding its underlying causes.The so called chin dimple is medically called cleft mentalis muscle; the two bellies of the mental muscle split apart in the midline and fail to join intimately in order to build a nicely shaped dome; when this happens the central chin skin lies direcly over the chin bone.Quite often, not always present and never in the same grade when it is present, the shape of the chin bone is a serious contributor to this odd shape, and this has to be explored; to begin with with a plain X-Ray film of the chin (frontal and lateral), in some peculiar cases a 3D Scan reconstruction might be necessary.When the bone is part of the problem some kind of osseous genioplasty has to be applied; in all the cases an intraoral approach allows direct muscular surgery to bring the bellies of the mentalis together to the midline (sutured), w/wo adding some interpositional graft to fill the remaining gap.If you wish better grounded opinion well lit, focused and standard images have to be assessed: frontal, both lateral and both oblique views, also from underneath.
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You have beautiful lips and a nice feminine proportionality. If you chin is not recessed, I would stay with the many attractive movie stars and celebrities that are famous for their cleft chin...I have over a dozen patients ask if I could create a cleft chin for them. Beauty is not being average  

I agree with the other suggestions. 
Get the diagnosis, treat the cause(s) and never inject liquid silicone anywhere.
The dimple may be dynamic (move with or be caused by muscle motion). If this is the case Botox will likely need to be included in your treatment plan.
Most dimples can be filled with a temporary filler such as hyaluronic acid. If you are pleased with this you may try something longer lasting such as fat transfer.

Best wishes,

Alexander Anzarut 

I would start out slowly and try a filler like Juvederm which is reversible if you don't like it. Botox is also a possibility with surgery being the last choice. 

Chin dimples can sometimes give a masculine appearance to the jaw.  A deep chin dimple can result from the anatomy of the mandible, or a deep recess between the bellies of the mentalis muscle.  A deep dimple is difficult to totally fill.  Patients should know that a correction will be made, but that the dimple will not totally disappear.   To soften the the chin dimple and rejuvenate the chin, I have used injectable fat or hyaluronic acid (HA) fillers (juvederm, perlane, restylane, or belotero).  HA fillers are all temporary solutions, as all get absorbed by the body.  Fat also gets absorbed by the body, but some fat should survive.  Serial injections of fat can have some long standing, potentially permanent results.  I recommend that patients start with this technique first.To fill a very deep depression, a small amount of skin and fat can be harvested from a well hidden incision.  This dermal fat graft can be placed through a small intra-oral or sub mental (below the chin) incision.   Neurotoxin (Botox, Dysport or Xeomin) injection into the depressor anguli oris (DOA) muscle can help with some of the dynamic wrinkles that occur on the chin when the patient depresses the lip.  I have not found these neurotoxins to be useful for chin dimples.I have seen a lot of problems with silicone injections, and do not recommend them anywhere for cosmetic reasons.  The silicone is spread throughout the soft tissue, and can become infected or inflamed.  Patients can have recurrent granulomas and present with firm, red, painful inflamed areas where the silicone was injected and dispersed.  In many cases, this silicone has to be repeatedly cut out as it becomes re-inflamed.  This leaves terrible scarring and can be extremely deforming.  I do not know of any Board Certified Plastic Surgeons who presently perform silicone injections to the face, buttocks, or the breast.Make sure that you see a board certified plastic surgeon. 

A physical exam will help with this, but muscle plication and fat grafting is usually a good treatment combination if this is superficial in nature.  Kenneth Hughes, MDLos Angeles, CA

The dimple is typically genetic in origin; and can be primarily due to the shape of the underlying bone; as well as the muscles which 'separate' in the midline. Once you determine the 'cause' you can either use fillers, a change in the contour of the chin bone; or 'sewing' the muscles together to alter the dimple. 

If you are sure you don't want your chin dimple, I recommend the temporary use of an injectable
filler in the chin. Hyaluronic acid is a safe and natural non-surgical option
where a patient can quickly and easily see the actual
results of a more balanced profile. Patients can resume normal activity after treatments. Some patients may experience mild swelling for
up to 7 to 10 days. The cost is reasonable and depends on the area you live in.