I had trauma to my left front tooth and the one next to it at the age of 10. They were both root canaled and then one was crowned which had the chip from the fall. I am now 29 and had a chronic abscess above the left front tooth turned out to be a cyst at the root. The endo cleaned it all out and added retrograde filling to the root tip. He then packed the area with biological osseous filler to replace some bone loss due to the cyst. My question is when the endo saw the end of the root, there was a smaller than hairline crack within the root canal. Just wondering even though the area was filled with the retrograde filler and bio stuff, is infection recurrence inevitable? I want to keep my own teeth! Especially my front ones.