Have your license number ready:

The patch will de-activate your Tooth Atlas, but you will be able to re-register using your original license number (which you probably got off the back of your CD case). If you can't find your license number, contact support@ehuman.com

Clear your caches:

Clear your browser's cache on all platforms / browsers

Clear your Java cache on PC or Mac

In Snow Leopard, Safari defaults to running Java in 64-bit mode. To enable the 32-bit Java required by the Tooth Atlas:

1) Quit Safari

2) In the Finder, go to the Applications folder and Get Info on the Safari icon (right-click OR hold the CMD/Apple key and press I)