Yes. But it depends on what you mean by each sentence starts a new paragraph.

Take a copy of your document.

Press Ctrl+H to get the Replace dialog.

In the find box type ^p.
In the replace with box, press the space bar once.

Press Replace All.

You now have a document with no paragraph divisions.

This is probably not what you want but may give you some ideas.

Is there some way to tell when you have a real paragraph break?