Can an apico incision cause the failure of a root canal on ANOTHER tooth?

Five years ago my dentist did a simple root canal on #10 (I think that's the number; it's the first tooth to the left of my front left tooth.)

One year ago, an endodondist performed apicos on #12 and #5.  They healed beautifully.

Now, one year later, I noticed that #10 was starting to feel a little funny under the crown.  When I went to my endodontist for my follow-ups for #12 and #5, I asked him to check that other tooth out.  He x-rayed it and said he noticed some very minor irritation along the root, did some "tapping" tests (which I didn't feel any real problems) and told me that it is possibly in the very very early stages of failure and that it might eventually also need an apico (he said another root canal wouldn't be effective).  He said it was minor enough at this point to let it go and just keep an eye on it with my dentist.  I got to my dentist for another matter in a few weeks and will have him start checking on it.

When I went home and started looking closely at the gums, I noticed that the small scar from my apico showed that the incision went directly over the root of #10.  That got me wondering.  Is it at all possible that having that incision over #10 along with that root being exposed to open air briefly one year ago could have maybe started it down the road to failure?  
I've had six root canals.  Two have failed, one is now possibly failing.  Maybe I'm just prone to this and that is it?

Any advice would be appreciated.  Thanks.

[Jerome Bogin, D.D.S.]

I do not feel that the apico on the adjacent teeth had any effect on tooth #10.I also feel that there is no propensity for a patient to have failed root canals.

[mike1105]

doubtful.