Dialogue can be used to vary pace (as long as you set this up in advance. For example, Character A is a fast talker, Character B slow one. You can make the point here by showing early on Character A always trying to finish Character B's sentences for them - and this is just to name one example of what can be done).
I have to watch things when writing diagloue because I love setting conversations up between characters but it all has to be relevant to the story.