disallowed Content

I have just updated to the latest version 4.4 to make use of the disallowedContent filter. This works great to prevent disallowed content being pasted into the editor, and when adding disallowed content into source view and switching to design it stips it out.

My issue is when adding content and the pressign my submit button the disallowed content is not stripped out. How can I run this fucntionaliuty on the click of my save button?

Thanks