Is there anything I can do to get nipple sensation back?

Thank you for your question.  After this amount of time, it is not likely that the sensation will return.  I'm sorry you feel it was a mistake, unfortunately this does happen to small percentage of women and can be a side effect from breast augmentation. If you would like additional information regarding breast augmentation, you can download a free copy of my Breast Augmentation Planner at ABetterBreast.com.Best of luck to you. 

Nipple sensation can change (hyper\hypo sensitivity). It is very uncommon for nipple sensitivity to not return at all. After 15 years it is very unlikely it would return. A possible solution would be to decrease your implant size but there is no guarantee. Speak with a board cerified plastic surgeon.  

After 15 years it is very unlikely that it will ever return. I do not think that a nerve that has been stretched for that long or maybe even cut will come back. You can seek some advice from several surgeons but I do not think you will ever get the sensation back.

and there are no signs that it is trying to heal such as tingling, its not likely to return ever.  I'm sorry you think it was your biggest mistake and I hope you have received other benefits of having had your augmentation to help offset the loss of sensation.  I would not encourage you to pursue procedures unless that person could nearly guarantee that you would have the results you desire.

If the 4th intercostal nerve is intact, you would need to place the implants under the chest wall muscle and or decrease the size of the implants. If the 4th intercostal nerve is not intact, it can often be repaired with microsurgery in an attempt to restore nipple and breast sensation.