The Hesperian Society has quite a few health care
guides, designed for health
workers in less developed areas:
Books and Resources | Hesperian Health Guides
They first came to mind here as they are the ones who created the book "Where there is no dentist", which was the first thing I thought of when I read the title:
Hesperian Books: Where There Is No Dentist PDF
That is a link to the page where you can purchase
the book. At the bottom of the page is the link to downloading all of the chapters free.
You can also read the book online here:
Where There Is No Dentist - Hesperian Health Guides
Anyway, the PDF's of these are all over the internet
and no reason not to have them when cruising. If you are fortunate enough to have additional finances a small donation to Hesperian would help as they do a pretty good job IMHO.