Well I just went through security at LAX and my titanium micro chip did indeed set off the scanner alarm and I got patted down as a result. Disgusting.
If you're asking about that titanium micro-clip that's inserted as a biopsy marker during a needle biopsy, then, I would say that it would do no harm to mention it when you're about to have any kind of diagnostic exam that involves your breast. I bring up the fact that I have the micro-clip... every time I undergo a mammogram.
As for airport security... I, personally, have never set off any alarms. And, have never broached the topic with airport security. But, if you feel that it warrants mention; or its appearance warrants an explanation, then go ahead and inform the attending TSA personnel.