https://www.desmos.com/calculator/jsxvbwl4kn

For my face I used many ellipses, hyperbolae and a couple circles. I also found a way to make the edges of an ellipse “sharp” (increase the degree of the y or x), to make the two teeth. I also stretched my face, which made me look a bit different. I left some of the lines different colours so you can see where the graphs were to show my thought process in how to build the graphs.