This weekend I changed the plugs for the first time on my 2005 5.4 after 120,000 miles. Followed the guidlines in the TSB to get the plugs out. I had two break off. I had the Lisle Ford Broken Spark Plug Remover LIS 65600 on hand. The tool worked great accept when pushing the ceramic insert down into the sleeve it caused a small piece of the side electrode to break off and go into the cylinder. Nothing else went into the cylinder. I attempted to get the piece out with a magnet and then with a vacuum. No luck with the magnet and not sure if the vacuum was successful (no borescope). At the time I didn't think such a small piece of debris would be a big deal and got comfortable running the engine anyway. I've put probably about 30 miles with no problem. Now after giving it more thought I'm very worried that I may have screwed up by not being sure to get the small piece of metal out. The metal piece was a small thin portion of the lower electrode, probably 3/16th long by 1/16th wide. It was quite thin (~1/32) due to 120,000 miles on the plugs. I know the best thing would have been to have no debris what so ever. Did I screw up? Would I have seen a problem already if I was going to? Or is this something that will cause damage over time? Anything that I can do now to avoid any future damage? Thanks for any input you may have.