Thank you for your question. It's not uncommon to observe changes in the lower face shape following orthodontic treatments like braces. The adjustment of teeth alignment can sometimes impact the overall facial aesthetics, potentially leading to what you've described as a 'sunken' appearance. The good news is that there are effective cosmetic approaches to address this concern. A popular and minimally invasive option is the use of dermal fillers. Fillers can help restore lost volume and improve facial contours. In particular, Sculptra, which is a poly-L-lactic acid-based filler, or Hyaluronic Acid (HA) fillers, are excellent choices. They can provide a natural and rejuvenated look, subtly enhancing the facial structure affected by orthodontic treatment. If you're seeking a more durable solution or if fillers do not achieve the desired outcome, fat transfer is another option. This procedure involves using your own body's fat, harvested from another area, to add volume to the face. It's a natural, longer-lasting alternative that can provide significant improvements in facial fullness and symmetry. I recommend a personalized consultation to assess your specific needs and determine the most suitable treatment plan. It's important to consider all options and choose what aligns best with your aesthetic goals and lifestyle.