GCSC Dental Anatomy Test 6 updated
actual questions and CORRECT answers
Which tissue shows the highest percentage of inorganic matter? - CORRECT
ANSWER Enamel, 96% inorganic
The enamel forming cells arise from what embryonic cell layer and are called what? -
CORRECT ANSWER arise from the ectodermal cell layer and are called ameloblasts.
Is dentin a vascular tissue? - CORRECT ANSWER no its avascular
Dentin is composed of what % inorganic and what % organic material. - CORRECT
ANSWER 70% inorganic
20% organic
What is the normal composition of enamel? - CORRECT ANSWER 96% Inorganic
(Calcium hydroxyapatite Crystal) are major part.
4% organic (material and water)
Odontoblasts are responsible for the formation of what tissue? - CORRECT
ANSWER Dentin
Where might you find mamelons? - CORRECT ANSWER On newly erupted incisors
The dentinoenamel junction (DEJ) is formed when... - CORRECT ANSWER When
enamel and dentin meet. It is a ridge between the two tissue types that allows the increased
adherence between them, adding strength of the junction.
Which zone contains fewer cells than the odontoblastic layer and is the location of the nerve
and capillary plexus? - CORRECT ANSWER Cell-free zone
, What is the portion of the pulp location in the root area? - CORRECT
ANSWER Radicular pulp
What is the largest group of cells in pulp? - CORRECT ANSWER Fibroblasts
Why do enamel spindles occur? - CORRECT ANSWER They result from odontoblasts
that cross the basement membrane before it mineralized into the DEJ
After the ameloblasts are finished with both enamel apposition and maturation, they become
part of the: - CORRECT ANSWER Reduced enamel epithelium (REE)
What is the size of each ameoloblasts in micrometers? - CORRECT ANSWER 4
Micrometers
The crystalline formation of mature enamel consists mainly of... - CORRECT
ANSWER Calcium hydroxyapatite
Define caries, erosion, attrition, abrasion, and abfraction... - CORRECT
ANSWER Caries: Loss through chemical means (acid) from cariogenic bacteria
Erosion: Hard tooth tissue loss by chemical (acid) means not involving bacteria.
Attrition: Hard tooth tissue loss caused by tooth-to-tooth contact, normal wear, during
Mastification or parafunctional habits.
Abrasion: Hard tissue loss caused by friction (Mechanical) from toothbrushing and/or
toothpaste. Located facial, cervical area. Canines commonly affected because of position.
Abfraction: Hard tooth tissue loss from tensile and compressive forces during tooth flexure.
actual questions and CORRECT answers
Which tissue shows the highest percentage of inorganic matter? - CORRECT
ANSWER Enamel, 96% inorganic
The enamel forming cells arise from what embryonic cell layer and are called what? -
CORRECT ANSWER arise from the ectodermal cell layer and are called ameloblasts.
Is dentin a vascular tissue? - CORRECT ANSWER no its avascular
Dentin is composed of what % inorganic and what % organic material. - CORRECT
ANSWER 70% inorganic
20% organic
What is the normal composition of enamel? - CORRECT ANSWER 96% Inorganic
(Calcium hydroxyapatite Crystal) are major part.
4% organic (material and water)
Odontoblasts are responsible for the formation of what tissue? - CORRECT
ANSWER Dentin
Where might you find mamelons? - CORRECT ANSWER On newly erupted incisors
The dentinoenamel junction (DEJ) is formed when... - CORRECT ANSWER When
enamel and dentin meet. It is a ridge between the two tissue types that allows the increased
adherence between them, adding strength of the junction.
Which zone contains fewer cells than the odontoblastic layer and is the location of the nerve
and capillary plexus? - CORRECT ANSWER Cell-free zone
, What is the portion of the pulp location in the root area? - CORRECT
ANSWER Radicular pulp
What is the largest group of cells in pulp? - CORRECT ANSWER Fibroblasts
Why do enamel spindles occur? - CORRECT ANSWER They result from odontoblasts
that cross the basement membrane before it mineralized into the DEJ
After the ameloblasts are finished with both enamel apposition and maturation, they become
part of the: - CORRECT ANSWER Reduced enamel epithelium (REE)
What is the size of each ameoloblasts in micrometers? - CORRECT ANSWER 4
Micrometers
The crystalline formation of mature enamel consists mainly of... - CORRECT
ANSWER Calcium hydroxyapatite
Define caries, erosion, attrition, abrasion, and abfraction... - CORRECT
ANSWER Caries: Loss through chemical means (acid) from cariogenic bacteria
Erosion: Hard tooth tissue loss by chemical (acid) means not involving bacteria.
Attrition: Hard tooth tissue loss caused by tooth-to-tooth contact, normal wear, during
Mastification or parafunctional habits.
Abrasion: Hard tissue loss caused by friction (Mechanical) from toothbrushing and/or
toothpaste. Located facial, cervical area. Canines commonly affected because of position.
Abfraction: Hard tooth tissue loss from tensile and compressive forces during tooth flexure.
