Google launched improved public URL removal tool to make it easier to request updates based on changes on other people's websites.
This tool is useful for removals on other peoples' websites. You could use this tool if a page has been removed completely, or if it was just changed and you need to have the snippet & cached page removed. If you're the webmaster of the site, then using the Webmaster Tools URL removal feature is faster & easier.
You can remove complete pages if the page is actually not live or blocked to spiders. You can remove content from a page if the content shows in the Google cache and is not live on the page.