Hagfish teeth

The other day at Ichtiology lab we had to draw the external and internal anatomy of a hagfish (Eptatretus bischaffii) and knowing that they throw the fishes away after being opened I took off the teeth of the one they gave to us and decided to clean them :] They have four rows,  two big ones and two smaller ones that go between the big ones. (By the way, sorry for the bad quality, the only camera I have is the one of my cellphone that kinda sucks for taking detailed pictures DX)