Enamel,dentin,and pulp develop from enamel organ.Enamel is derived from ectoderm whereas dentin and pulp are derived from mesoderm.
A) Both statements are true. B) The first statement is true;the second statement is false. C) The first statement is false;the second statement is true. D) Both statements are false.
Pulp tissue consists of blood vessels,lymphatic vessels,nerves,fibroblasts,and collagen fibers.The nerves of the pulp are primarily sensory and transmit both pain and thermal sensations.
A) Both statements are true. B) The first statement is true;the second statement is false. C) The first statement is false;the second statement is true. D) Both statements are false.
Each of the following is true of enamel lamellae EXCEPT one.Which one is the EXCEPTION?
A) Lamellae are cracks in enamel that rarely extend through enamel. B) Enamel lamellae may provide a pathway for bacteria into enamel. C) The most common type of lamellae is caused by trauma. D) Rapid changes in temperature from food and drink commonly cause lamellae. E) An infrequent type of lamellae is a developmental defect.