I’m not a dentist, but I don’t think you need a root canal. You may need a crown if the tooth is broken and/or can’t be re-filled though. That’s usually what happens after a tooth which was once repaired with a filling can’t be filled again.

this basically sums up what i wanted to say…
If the tooth is sensitive to heat but relieved by cold — if hotter liquid, for example, makes it hurt and colder liquid seems to ease or eliminate the pain — this generally points to nerve damage, but not always.
Similarly, if the tooth is sensitive to pressure (as in pushing it toward the jawbone with a fingertip), this is another indicator of possible nerve damage… but again, it’s not conclusive.
Following a period of extra-careful cleaning with a soft toothbrush, lots of salt water, and, if at all possible, use of the special cannula tip) — if the symptoms persist and both above tests indicate “trouble” you may need to see a dentist.
Before anything is done… insist on a thorough diagnosis of the situation. If a dentist has been consulted to help determine the need for a root canal, be sure the following steps are taken:
Careful visual exam of the teeth (looking for color change).
Checking for temperature sensitivity (hot/cold).
Observing any additional sensitivity to pressure; either from biting, tapping or pushing on the suspect tooth.
Carefully X-Raying the area(s) in question. Don’t allow the dentist to prescribe a root canal only from X-Ray diagnosis, because they are often non conclusive in this regard. Many teeth that “showed need,” on X-Ray, for root canal treatment, subsequently healed without it.
The tooth should be checked with an electronic nerve tester: A simple device that measures the nerve’s ability to react to a mild electrical stimulus.
If your dentist has not checked the nerve in this way… and is recommending a root canal… it would be best for you to discuss this with the dentist. If he does not readily offer to do the test do not, under any circumstances, permit the start of root canal treatment …
…because, once treatment begins, you are totally committed: You cannot change your mind and ‘back out’ halfway through the treatment.
If all five methods of checking all heavily indicate the need for a root canal you can be about 99% sure it’s necessary.
If any one or two of the indicators are not conclusive it’s generally best to wait for a while. In many cases the situation will “settle down” and resolve itself.
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here you should read up on it if your teeth are sensitive its fun! lol
il research some articles for you guys one sechttp://hubpages.com/hub/Sensitiveteeth
k its pretty good i hope you read :]