Getting naughty with images - Tooth fall

Start by opening an image with grinning kids.

Create selection of a tooth using polygon lasso tool.
Press Ctrl+Shift+J to cut paste the selection in a new layer. it will create the hole in the image.

Create a new layer below the image layer. Fill with a solid color as shown in the image below. This color will show through the hole.
Select brush tool and create a little shadow effect using a darker shade of the color.
Select the tooth layer. Create several duplicates. Move and rotate the duplicate layers as shown below.
Open animation window. For the first frame let the tooth layer be in it's original position covering the hole.
Duplicate frame. Hide the original tooth layer. Unhide the next position of duplicate tooth layer.

Repeat the above mentioned steps till the tooth falls beyond the bottom edge of the file. Duplicate last frame and hide tooth layer.

Press Ctrl+Alt+Shift+S to save an optimized animated GIF.