Lab 18 - Image 17

Occlusal surface of equine incisors. 1, a cup, an asterisk marks the infundibular lumen which is filled with black debris; 2, a large recently formed enamel spot; 3, a cup that is almost an enamel spot; 4, a small enamel spot that is nearly gone; 5, enamel layer; 6, dentin (light yellow and brown), 7, dark secondary dentin; 8, light tertiary dentin surrounded by secondary dentin; double arrow shows the extent of a dental star = light core of tertiary dentin surrounded by darker secondary dentin. Secondary and tertiary dentin gradually fill the pulp cavity as the tooth shortens due to wear (dental attrition).