Plugin can't seem to write to page.php

I’ve installed two plugins, AddThis and SlideDeck, both of which, if enabled, add code to a page in order to make them work. AddThis adds its sharing button code, and SlideDeck adds some JS. But neither are showing up on the site. It works locally, and when I view the source locally I can see the code being added, but not on the live version.

It had a permission of 644 but the rest of the theme fiels had 664, so I changed it but no luck. I looked at permissions of other directories but they all appear to be what they should be.

I’m not sure what to do next. Any help much appreciated!