Will dermal fillers fix my masseter muscle causing an asymmetrical jawline? (Photo)

First, let me say that I am sorry you have been made to feel this way. Happily, at least from the photo, it appears to be a rather simple, quick and relatively inexpensive issue to address in a matter of minutes. From what I can see your left side frankly appears to be a strong masculine jaw. For that reason, I would be reluctant to treat the masseter muscle on that side with a neuromodulator, such as Botox. Instead, I would suggest instead volumizing the depression, the "slump" on that side with a volumizing filler. In my NY office, I would choose Juvederm Ultra Plus XC for this purpose. In my Israel satellite facility, where a far greater number of regulatory agency approved injectable volumizers are available, I would opt for Princess Volume, Aliaxin SR, or Stylage XXL for this purpose.  I would suggest that you seek consultation and treatment from a board certified aesthetic physician and make sure to ask to see his/her personal before and after photos before agreeing to proceed. Your physician might first suggest a test filling of the depression with normal saline or diluted anesthetic solution to give you a five or ten minute chance to see how the actual result might look with actual volumizing filler. Best of luck to you.

Botox in combination with radiofrequency treatments can be used to slim the jawline on one side - and injectable fillers (like Revanesse Versa, Radiesse) and Sculptra can be injected on the bone on the other side to get more lift and shaping, resulting in a more defined, structured jawline. I suggest getting a formal evaluation with a facial sculpting expert. Best, Dr. Emer.

If it is a muscle imbalance then selected use of botulinum can even it out a bit.  The most definitive thing is to have the bone reduced which is procedure done through the inside of your mouth. It's a permanent improvement.

There are numerous options in management of jaw symmetry. I annot adequately assess whether the asymmetry is muscle or bone related from a photo. In either event, the larger side can be reduced - with Botulinum toxin to reduce the muscle bulk or operative bone reduction. Or (and this would be my preference since the strong, square, masculine jaw is generally considered aesthetically desireable in men), the "slumped" side can be augmented using hyaluronic acid filler (Voluma, Juvederm Ultra Plus or Revanesse Versa) or calcium hydroxapatite filler (Radiesse) and/or collagen stimulation/remodeling with Sculptra, PDO threads, and/or fractional radiofrequency (Morpheus8). An implant, placed operatively by a plastic surgeon could also be considered.
I hope this is helpful. Good luck.

Renato, You can approach this in two ways or a combination of both. I would start with trying to shrink the masseter on the large side with Botox/Dysport/Xeomin. If need be you could add filler to other side later. One thought-If you chew gum on one side all day long you could be strengthening one side over the other but I have not seen this much difference from chewing.