Gordon, I think you're talking about 2 different games.
In Monkey Island IV: Escape from Monkey Island the game opens with Guybrush tied to a mast of a pirate ship and he kicks over a container of hot coals.
The sequence of the tooth being knocked out in a barber shop is in Monkey Island III: Curse of Monkey Island. That game opens with Guybrush a prisoner in the hold of LeChuck's ship, but he's not tied up so his escape doesn't involve burning through ropes.
Hope this helps.