TCDHA Histology Midterm-Final Review Questions and Answers (Graded A+)

What is enamel? - ANSWER-Hardest calcified/mineralized tissue in the human body Covers Anatomical crown What is the blood supply of enamel? - ANSWER-Avascular and non-vital (has no nerves) What is the material makeup of enamel? - ANSWER-96% inorganic (mineralized) material - mainly calcium hydroxyapatite 3% water 1% organic - enamelin (protein component) What color is enamel? - ANSWER-It is grayish/bluish white but appears slightly yellow b/c its translucent and the underlying dentin is yellowish What is amelogenesis - ANSWER-Process of enamel matrix formation Where is enamel matrix derived from? - ANSWER-Enamel matrix is ectodermal and is derived from inner enamel epithelium (IEE) of enamel organ What stage does amelogenesis occur in? - ANSWER-During the appositional stage (formation of enamel/dentin matrix) of tooth development What is enamel matrix composed of? - ANSWER-At first is composed of proteins, carbohydrates and small amounts of calcium hydroxyapatite crystals it DOES NOT contain proteins like dentin, cementum and alveolar bone What must be present in amelogenesis? - ANSWER-Dentin must be present Where is enamel first formed? - ANSWER-Enamel is first formed in the cusp/ tip area of a tooth Ameloblasts - ANSWER-Produce enamel matrix Tomes process - ANSWER-- secretes enamel matrix - 6 sided pyramidal shaped projection of ameloblast facing DEJ ( guiding factor of laying down enamel) Where is enamel present in? - ANSWER-It is present on the anatomical crown area ONLY Enamel pearl - ANSWER-Small, spherical enamel projections on root surface Enamel dysplasia - ANSWER-Faulty development of enamel Deepened pits and fissures - ANSWER-Is common and occurs when ameloblasts back into one another during stage of apposition, cutting off their source of nutrition, which causes incomplete maturation of enamel matrix (These areas may become target areas for dental caries) Sealants - ANSWER-used in the prevention of caries What is mineralization? (Complete/incomplete/immediate/not immediate) - ANSWER-It is complete and immediate