Which procedure would allow me to achieve a more sharp and defined jaw line? (photos)

For a more defined jawline to strengthen your profile (and help prevent the dreaded jawline "jowl" sagging), we use injectable fillers like Revanesse Versa - a filler known to limit swelling and give subtle, soft enhancements - or Radiesse. Using a cannula to limit pain and swelling, we inject on the bone in strategic points to get more lift and shaping, resulting in a more contoured lower face and defined, structured jawline. I would suggest getting a formal evaluation with a facial sculpting expert. Best, Dr. Emer

Thank you for sharing your photo. Looking at your chin and jaw line, I would recommend chin and Jaw Line Lipo with skin tightening with a non surgical neck lift with the MyEllevate neck system. My recommendation is based on that you have some fat on the chin and jawline you also appear to have lax skin under your jawline that would benefit from tightening. Wishing you the best of health.

Thank you, Red_Bird for your question and photographs.
Photographic evaluation is incomplete without personal examination to give the most appropriate answer
However from the photographs, it seems that,
Morpheus8 and Kybella are both good options.Morpheus8 will also give you a good skin-tightening effect as it works similarly to HIFU. The ultrasound will induce more collagen synthesis in your skin thus also tightening your skin and reversing your skin laxity. In case of your TMJ disorder, Botox treatment will help lessen your problem.

Please consult a board-certified dermatologist near you and discuss this in detail.
Wish you an alluring look

Much more information is needed, such as a full set of facial photographs including your neck from different angles in a chin neutral position. It would be also helpful to know your age. If you're considering losing additional weight, that should occur first before any surgical intervention. You also appear to have significant fat deposits located both above and below the platysma muscle in the neck.

Most plastic surgeons will most likely recommend liposuction as the gold standard for the removal of excess subcutaneous fat.
That said, it doesn’t look like you have a lot of excess fat in your neck.
Contour of this area is highly dependent on what the shape and size of the mandible is. having a projecting chin doesn’t mean you have an appropriate size mandible. The body of the mandible can be small with at the same time having a projecting chin. When the mandible lax sufficient length the underlying platysma muscle test draped in neck in the more oblique fashion. I’m not sure fat removal is going to get you the results you’re hoping for.
Personally I recommend liposuction if someone needs reduction of subcutaneous fat.
I don’t think your issues are related to access subcutaneous fat.
Consider having a few consultations with local plastic surgeons and oral surgeons. oral surgeons tend to see things from a bone perspective by plastic surgeons usually are more soft tissue oriented. Both specialties contribute to work in this part of the face.
Best,
Mats Hagstrom MD