This is a separate stream of binding that prioritizes aesthetic over all else.
It involves often drastic changes, replacements and substitutions to restore the book to as new an appearance as is possible, or change the book to a different structure entirely. This is a big call for a book, and requires much thought. I rarely undertake or advise this option, as it is so drastic.
Sometimes though, it is appropriate.
Search the tags on the sidebar to see restoration projects on the blog.