Weak Chin - Jaw Surgery Vs. Chin Implant?

The first thing is you need a correct Diagnosis, do you indeed have a weak chin from a small lower jaw or do you have an isolated weak/small chin. Considering you acknowledge your underbite, you likely have a small/retrognathic mandible. So your best option would be to see a plastic surgeon whom is familiar with tooth/skeletal relationships to discuss your options. Not all plastic surgeons are the same with regards to this topic, do your research and find one who can and routinely performs either corrective jaw surgery or placement of chin implants. In regards to your TMJ pain, your malocclusion (underbite) is likely contributing to this, correcting your occlusion orthodontically would be a good place to start so having a consultation with an orthodontist would be another valuable consult for you to help you decide what your best options would be.good luck

It's best to begin by consulting with a surgeon in-person to discuss your options. During your initial examination, your #chin will be evaluated along with the neck and jawline. A weak #chin implies a lack of chin support for the skin along the neck line. In younger individuals a chin implant alone is usually all that is needed to improve the appearance of the neck. Subsequently, it will also improve the overall #balance of the face and can create the illusion of a smaller nose. As a stand-alone procedure, chin augmentation can be performed in the office under local #anesthesia. For individuals with signs of #aging in the neck, a chin implant added to one of the recommended procedures above, will provide optimal results.
If you are not a candidate at the time of your #consultation, your board certified plastic surgeon can recommend alternatives to address your concern. Consulting with a board-certified plastic surgeon who specializes in #face, #neck and #chin procedures is important to ensure you are receiving the best advice, care, and surgical experience possible.

You seem to be an ideal candidate for Chin Implant Surgery. You would have improvement in the appearance of your chin and jawline. This would also have the added benefit of making your nose look smaller. Chin Implant surgery is relatively inexpensive, and takes less than 30 minutes. Downtime is about a week, and your results are permanent.
I'm not a big fan of sliding genioplasty surgery (surgically advancing your chin-bone forward).
I've attached a link to my Chin Implant photos for your perusal.
I hope this is helpful for you.

While I perform both bony surgery to improve the chin, as well as implants, I generally favor implant surgery. A chin implant is a short, out-patient surgical procedure with few complications. Cutting the chin bone itself is a much bigger operation which I would hesitate to recommend, unless there was no alternative.
As a plastic surgeon with both a medical and dental degree, I have performed many operations on the jaws to move the bones, including the jaws and chin, but surgery on your jaw may not improve your TMJ problems and you should consider that fact in your decision. My gut reaction in looking at your photo would be to opt for a chin implant. If you did a chin implant, you are not burning any bridges, and could still do jaw/chin surgery at a later date.
To simulate what it might look like, I frequently inject sterile water into the patient's chin and you can immediately look at it in the mirror.

In many instances jaw surgery can accomplish both goals. However, traditionally these are different surgical proceduress. TMj surgery typically does not improve chin projection whereas a SSO for malocclusion or sliding genioplasty can definitively achieve chin enlargement. The use of submental liposuction can enhance the result as well.

In this
situation, it is not wrong to think of orthognathic surgery as a two for one
type procedure.  Advancing the lower jaw
with bone grafts or implants will alter the projection of your chin while possibly
alleviating your TMJ symptoms at the same time.  After the jaw augmentation if the chin projection is not corrected
sufficiently a chin augmentation can be done at the same time.  However, without a physical exam it is
difficult for me to say definitively whether or not you would still require a
chin implant in conjunction with the mandibular advancement.  Be sure to confirm that your doctor is a
board certified oral maxillofacial surgeon before your consultation.  It would also be helpful to obtain any recent
imaging studies you may have from a dentist or orthodontist and bring them to
your consultation.Be well and
good luck!@norrisplastic

This would be a good option. you would be getting both of these things done at the same time given that moving your jaw forward is the answer.
 

A small to medium-sized chin implant placed through a submental incision would give a stronger chin profile. Mandibular osteotomies or open jaw surgery could also strengthen your chin. However, neither of these two procedures will address nor improve your TMJ issues.Chin implants are inserted throughout sub mental approach as an outpatient surgical procedure under local anesthesia. Mandibular osteotomy is performed under general anesthesia and usually requires a 24-48 hour stay in the hospital. If the teeth are out of alignment significantly, this may be the best route to proceed with. For many examples of chin implants, please see the link below to our chin implant photo  gallery

In looking at your photo, you appeared to be an ideal candidate for a nice chin implant. The procedure is very easy to perform in skilled hands. You should achieve an excellent aesthetic facial balance that would enhance your already beautiful face.
Unless you have a severe malocclusion problem necessitating major reconstructive or orthognathic surgery, I would strongly advise you to go with the chin implant. Except in cases of severe malocclusion, the TMJ entity is another matter unrelated to the cosmetic aspects of your chin. I would advise you to address the TMJ as a separate entity.

If your bite is not contributing to the TMJ pain. Then it is a chin implant and then deal with the TMJ. TMJ surgery will not affect the chin, surgery on the mandible may  improve the profile some.