Why do I still have nipple pain 6 months after partial capsulectomy?

Pain in the breasts in general after a breast augmentation usually indicates some degree of capsular contractrure.  Since you had a partial capsulecteomy, it's possible that the nerve to the nipple may still be entrapped in the part of the capsule that was not removed.  However, since this is a very specific nerve, and if the capsulectomy theory is true, then perhaps you are fortunate that that portion of the capsule was not removed because that could lead to total anesthesia of the nipple which would not be curable.I have seen nipple pain after a breast augmentation last over a year.  However I have never seen nipple pain that didn't subside and finally vanish over time.  I wish I had a simple answer for you, however there may be an analogy between nipple pain after a breast augmentation and finger painting after hand surgery.  If you were my patient, I would suggest desensitizing the nerve to the nipple by whatever means your plastic surgeon suggests.  I remember back when I did hand surgery, the hand surgeons would often recommend tapping the hypersensitive finger to desensitize it.  The recommendation I just espoused may be brilliant, and then again it may be total malarkey, but it is the best I can come up with on short notice.

The pain you are experiencing following capsulectomy and implant exchange is not uncommon, but not frequently seen.  When surgical intervention is accomplished, various small nerves are disrupted and then grow back haphazardly. Your "nerve" pain will get less intense and less frequent with more time.