About the larger than life-size Axis Scientific Decayed Teeth Comparison Anatomy Model: This educational model shows two enlarged cross sections; one healthy molar and one decaying molar. The healthy displays intact enamel healthy dentin and healthy pulp. The decaying tooth shows compromised enamel and dentin the decay continues its path into the pulp of the tooth. This model is perfect for comparing the internal structures of the tooth as well as the outside including the gum line.