There are two types of root systems. taproot system and the fibrous root system.
Monocot and dicot
My Doc said you can smoke after 2 Hrs of the treatment..
from http://wiki.answers.com/Q/Does_a_root_canal_hurt I can only speak from my experience but I had a root canal done on a molar 2 years ago and it was easier than a lot of fillings I've had done....
treatment options available include no treatment or extraction.
Root Canal Animation
How to Treat the Root Cause Naturally
Bermuda's Oceanside Spa
Jeffrey Herf's Template to Counter Criticism of Israel