Enamel

Question 1

Chemical Properties:

Answer 1

Calcium hydroxyapatite

Question 2

Formation: Enamel develops from the

internal enamel epithelium of the tooth germ meaning it is of…….

Answer 2

ectodermal origin

Question 3

Mature enamel is a highly mineralised or inorganic material, consisting of mainly ………..

Answer 3

calcium hydroxyapatite

Question 4

Enamel appears more ……… than either dentin or pulp because it is denser than the latter structures, both of which appear more radiolucent.

Answer 4

Radiopaque

Question 5

Surrounding the outer part of each enamel rod is the ……… or interprismatic region, which appears different from the rod core on cross section because of it different crystalline orientation

Answer 5

Interrod enamel

Question 6

The …….. appear as brown incremental lines in a stained section of mature enamel with different orientation depending on the sectioning of the tissue

Answer 6

Lines of Retzius

Question 7

Associated with lines of Retzius are the raised imbrication lines and grooves of the …………. , which are noted clinicially on the normastictory surfaces of some teeth in the oral cavity, and which can be lost through tooth wear

Answer 7

Perikymata

Question 8

The……… is pronounced incremental line of Retzius, which marks the stress or trauma experienced by the ameloblasts during birth, illustrating the sensitivity of the ameloblasts as they form enamel matrix

Answer 8

Neonatal line

Question 9

The dentinoenamel junction is a junction between mature enamel and dentin that appears scalloped on a cross section of a tooth, with the convex side toward the ……, and the concave side toward the enamel

Answer 9

Dentin

Question 10

The …….. are a microscopic feature of mature enamel and represent short dentinal tubules near the dentinoenamel junction that result from ondtoblasts that crossed the basement membrane before it minerlised into the dentinoenamel junction.

Answer 10

Enamel Spindles

Question 11

The …………. are a microscopic feature that are noted as small, dark brushes with their bases near the dentinoenamel junction in the inner one third of enamel, representing areas of less mineralisations.

Answer 11

Enamel Tufts

Question 12

The ……… are a micoscopic feature that represent partially mineraliseeed vertical sheets of enamel matrix that extend from the dentinoenamel junction near the tooth’s cervix to the outer occlusal surface

Answer 12

enamel lamellae

Question 13

composition of enamel ……..% inorganic and ….. %organic

Answer 13

95 % inorganic 5% organic

Question 14

Components of organic Enamel

Answer 14

Enamel Protein, water and lipid material