Not using the Pen Tool was a little tricky, but every time I caught myself using the Pen shortcut, I made sure to switch to the Pathfinder options while I constructed these teeth illustrations. I drew the original sketch a few years ago, and when this class came up, it provided a good starting point.
Sketch (excuse the super cool Instagram filter)
Illustrator, step one
I also watched Hayden's class on applying textures with Illustrator to bring more life to the teeth. Lighting and shading have always been difficult for me when it comes to drawing/illustration, but I'm pumped for the direction these are going.