Well there's one other way that can sort of work for one branch. You can set one branch so that it concludes with the end of the discussion, forcing the player to talk to the NPC again. Then you can set the button for that branch to disappear based off of Component Complete for the NPC.

That will only work for one branch though, and it will also require you to end the conversation (to trigger the change) and then force the player to talk to the NPC again.