I have been asked on a couple of occasions whether the Zeno Tip Cartridge can be reused. At first I did not definitely know the answer because the tip on mine had not yet expired. Now that it has, I can safely say that the answer is no.
When the device gets down to only a few uses left on the tip, the tip itself seems to quit heating up as effectively. I found that I was basically cheated out of my last 2 uses. Then it just quits and will not heat up at all. I took it off and put it back on to see it it would reset, and it did not. Basically, it appears to have a little chip in it that kills it after the set number of uses has run out.
I should also mention that even if I had found a way to re-use it, I would not recommend doing to. It really is best to follow the manufacturer's directions on such things. Regardless, I couldn't find a way to to cheat it.