Anyone have any experience with a cavity that might be root canal?

I went for my cleaning yesterday. I have had a sensitive area for a few months now, no one was able to find anything- nothing came up on xrays. The dentist blew air into it was very sensitive- so he said he will block out 45 min at my next appointment, numb me up and fill it, but how can a cavity be there if it is not showing up on the xray- he said he thinks it is right on the gum line, or I might need a root canal, and he will send me to a specialist if I do need one. I trust my dentist 110 % .I have had 2 root canals over the years and I knew I needed root canal , by the pain I was in. It was awful- the pain I experienced- I do not handle pain well , and am scared of pain. I have no pain just sensitive to cold liquids. Did anyone ever have this and it was just a cavity? I am freaking out- just not too thrilled I might have to go thru root canal and I am going on vacation in a few weeks. Thanks in advance if you read this far.

Message edited 3/15/2012 8:55:39 AM.

Re: Anyone have any experience with a cavity that might be root canal?

If he fills it and the sensitivity doesn't go away, you'll probably need a root canal.

I've had too many to count and only a few were horrific pain where I KNEW I'd need a root canal. Most were sensitive teeth that eventually got to be too much to handle.

Once he drills, he'll be able to tell if you need a root canal.

Better to get it done now, then to be on vacation when the real pain hits.