being that hes round, how about creating thin poly cylinder with 2 division on the end cap and the number of divisions along the axis to equal the teeth. scale the end cap faces until the outer ring is about the depth of the teeth. Turn "keep faces together" OFF then extrude upward a couple times, once for the gum line, once for the center of the teeth, and final time for the top of the teeth. scaling faces as need along the way. Then go in and tweek verts.