I went to the dentist today because of some bad pain in one of
teeth/jaw.

Essentially the nerve in the tooth is either dying/stunned/bloody
useless. There wasn't any sign of tooth decay, nor an abscess on the
xray done. Yet it takes the tooth a few secs before it responds to cold
and doesn't really respond to hot food/coffee. She though that it
might have been caused because I may (No idea if I do) grind my teeth
or from an old trauma.

What are the chances that the nerve won't die, and recover, or is
that wishful thinking? As I really don't wont a root canal done on
it. As the dentist said give it a week and see what happens.