Braces treatment for overbite correction changed my face shape

This is a great question and a very common complaint from a certain percentage of orthodontic patients. 

There are certain types of orthodontic treatments that will definitely cause facial changes; some are positive facial changes and some would be considered negative changes to the majority of the population. 

A doctor should NEVER begin orthodontic treatment before understanding the possible facial changes of the proposed treatment and discussing those possible changes with the patient.

In general, most bicuspid extraction treatment will cause a longer, narrower face with smaller lips, longer nose and weaker chin. The midface will often be underdeveloped causing a flattening below the eyes. The profile view of the face will also be seriously compromised as it will make the face look like an arrowhead.

Sometimes an orthodontic patient will have large, overly developed masseter muscles (facial muscles that are primarily used for mastication) because of their compromised bite. After orthodontic treatment the patient's bite is improved and stress is taken off of these facial muscles thus causing them to relax; which can give the face a more "sunken" appearance and more prominent cheek bones. This is a permanent facial change but is viewed by most as a positive change (no more chubby cheeks and beautiful high cheek bones). 

A serious discussion with your doctor about what specifically you are not happy about is in order. If bicuspid teeth were extracted then the fix is complicated and your treating doctor probably won't want to change course and more than likely wouldn't even know what to do (or he/she would have done it from the start).

Hope this helps. Good luck!