I just changed my spark plugs and one them was dented in like something inside the cylinder was hitting it. How hard is it to take off the drivers side head, to make sure the cylinder is clean?

 

How does a spark plug get dented

I've seen the ceramic break in half, but never dented? Could it have been a nasty detonation that did the damage (and nothing from inside the cylinder)?

 

I had never worked on a car before and I managed to make it through a heads/cam swap so I'm sure you'll be fine if you just follow guides and take your time. Good news is the drivers side is easier than the passenger side, since it's not connected to the big ol' accessory bracket.

 

The worst part is getting the exhaust manifold or headers off and out of the way so you can get the bolts at the bottom of the heads loose.

 

Don't pull the head ... unless your car was having major problems befor you pulled the sparkplugs. It's a big job. Not worth it. Just put in a new plug and start it up. Run it for a minute, then check that plug again. Hopefully it will look fine. Didn't need to pull the head.

 

I was thinking about doing what Mikey said. The plug wasn't dented, but the piece that goes up over the puck was pushed down into the puck, kind like something was hitting it.