In short, no you do not.
A DCN is one way of control, but if you have a small quantity of documents, a unique title is a perfectly acceptable identifier. If you have hundreds of documents a DCN would probably make it easier, but it is not mandatory.
You also do not need a rev history page as part of your document. The rev status may be indicated by a date, a version number/letter, or by other means. Your rev history may be maintained separate from the document in a log, a database or by other means.
Use what makes sense to you and works effectively for your business without adding unnecessary expense..
