I have a problem with chin dimpling when I close my mouth. I have a weakened chin. Can botox fix this? (Photo)

The mentalis muscle creates that unwanted dimpling along your chin, and 5-10 units of Botox can be used to effectively relax this muscle and eliminate the dimpling.  

Chin dimpling can be caused by muscle tension and overactivity. This can easily be alleviated with a small amount of Botox injected into the muscle. Typically this muscle overactivity can be indicative of lower facial skeletal disproportion, but Botox could easily treat the muscle complaint. Botox in the lower face can help with chin dimpling, down turned corners of the mouth, and masseter hypertrophy (square jaw).

Yes the dimpling in your chin is typically caused by over active muscles.  With time this can lead to the uneven appearance of the chin described as an orange peel in  medicine.  Botox or an equivelant toxin works very well in this area.  Find an injector who you trust.  Good luck!