During a game session ( a gaming night with your friends ), is it possible to exit the dungeon before you defeat the final boss, in order to heal wounds and buy equipments, and the reenter the dungeon?
And also refresh spells?
Using the rules as written, you cannot re-enter the same dungeon. I don't see why you couldn't house rule this though... especially for campaign play. The "Deeper Dungeons" expansion that is mentioned in the rules is supposed to add rules about going back to town and returning to the dungeon while also handling dungeons with more than one level (based on what I've seen Andrea mention on the yahoo group).