Recreate a new page now (just copy and paste html) and save.
Copy the HTML, paste that in a text editor, delete the pages and revisions and trash, create new page using the old html and same title and slug)
If you are comfortable with editing the database, it should be fairly straight forward. Posts, Pages and revisions are in the wp_posts table and can be sorted by post type (page, post, revision, attachment.)
Unless you have very many pages and posts or revisions, it is best to leave things in the db alone, just because a table has a line for a post revision, i.e, isn’t really slowing anything down, it might save a few hundreds of a second in a query on a large site to remove these.
When a bot indexes your site, it does not have db access so it just goes through your site’s publicly available pages and their links. A good tool to check for broken links is XML-Sitemaps.com
If your site was indexed when permalinks were not set as you desired, or you have removed content, etc., create a sitemap and have your robots.txt file point to it. The Search Engines will catch up eventually.