Roots cannot re-enter a joint that a cured liner has sealed, because the opening they followed is gone. They can still enter any other open joint on the line. That is why Nuflow DFW checks every joint on camera before recommending a point repair instead of a full lining.
The detail
Roots do not drill through sound pipe. They find an existing opening, usually an unsealed bell joint in clay tile or a corroded gap in cast iron, and follow the moisture in. A cured liner removes that opening permanently.
What it does not do is change the rest of the line. If the camera shows roots at one joint and hairline intrusion at two others, sealing one is a partial fix, and the same tree is still growing toward the same pipe.
The practical test: ask to see footage of the full run, not just the defect. A point repair is the right call when one joint is compromised and the others are intact. It is the wrong call when the line is opening up in several places.
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