Enamel, Dentine &Periodontium

Question 1

What is enamel derived from?

Answer 1

Ectoderm

Question 2

What are enamel-making cells called?

Answer 2

Ameloblasts

Question 3

What is the composition of Enamel?

inorganic, organic, water %

Answer 3

Inorganic (mineral) 95%
Organic (protein) 4%
Water 1%

Question 4

What is the enamel matrix made up of?

Answer 4

Amelogenin,
Ameloblastin,
Enamelin

Question 5

The dentine-pulp complex originates from?

Answer 5

Ectomesenchyme

Question 6

What is the compostion of dentine?

inorganic, organic, water %

Answer 6

70% inorganic
20% organic
10% water

Question 7

What are the lines of von Ebner?

Answer 7

incremental growth lines in dentine

Question 8

What is the granular layer of Tomes?

Answer 8

Located in the root of the tooth between dentine and cementum

Question 9

Where is the Tomes process?

Answer 9

Between the enamel matrix and ameloblasts

Question 10

Name the structures surrounding a dentine tubule

Answer 10

peritubular dentine and intertubular dentine

Question 11

The Apical foramen (at the end of the root canal) is where..

Answer 11

pulp and periodontal ligament meet &
nerves, blood and lymphatic vessels enter the tooth

Question 12

What are the lines of Salter?

Answer 12

growth lines of cementum

Question 13

What cells are found in dental pulp?

Answer 13

fibroblasts (most numerous)
odontoblasts (also in dentine)
macrophages (and other immune cells)
ectomesenchymal cells (become odontoblasts or fibroblasts when needed)
stem cells

Question 14

What is the subodontoblastic plexus of Raschkow?

Answer 14

Innervates the pulp, only in coronal pulp, not root

Question 15

What is GOMPHOSIS and what does it include?

Answer 15

Fibrous connective tissue “joint” between the tooth and the bone
Cementum
Alveolar Bone
Periodontal Ligament
Gingivae

Question 16

What is the composition of Cementum?

inorganic, organic, water %

Answer 16

inorganic (mineral) 65%
organic (protein) 23%
water 12%

Question 17

What are the three proteins in dentine?

Answer 17

dentine sialoprotein
dentine glycoprotein
dentine phosphoprotein

Question 18

What is the cell type responsible for Dentine?

Answer 18

Odontoblast

Question 19

What is the cell type responsible for Alveolar bone

Answer 19

Osteoblast

Question 20

What cell type is responsible for Enamel?

Answer 20

Ameloblast

Question 21

What cell type is responsible for Cementum?

Answer 21

Cementoblast

Question 22

What are two structures of Dentine?

Answer 22

Peritubular dentine,
Lines of von Ebner

Question 23

What are two structures of Alveolar bone?

Answer 23

Lacunae,
Osteons

Question 24

What are two structures of Enamel

Answer 24

Enamel lamella,
Rods and Interrods
Striae of Retzius

Question 25

What are two structures of Cementum?

Answer 25

Incremental lines of Saltar,
Cementocytes

Question 26

What are the 5 periodontal ligament fibre bundles?

Answer 26

Alveolar crest
Horizontal
Oblique
Apical
Interradicular (only in multirooted teeth)

Question 27

What are the 5 groups of Gingival Ligament Fibre Bundles?

Answer 27

Dentogingival (tooth-gums)
Alveolargingival (bone-gums)
Circular (around tooth)
Dentoperiosteal (tooth-bone)
Transseptal (tooth-tooth)

Question 28

Difference between succadaneous and non-succadaneous teeth?

3

Answer 28

-succadaneous replace deciduous teeth, non-succadaneous do not
-succadaneous teeth develop on the lingual extension of the deciduous tooth germ, non-succadaneous teeth develop from the posterior extension of the dental lamina
-succadaneous teeth include anteriors and premolars, non-succadaneous include molars

Question 29

What cells are involved in the shedding (exfoliation) of deciduous teeth and what do they do?

3

Answer 29

Osteoclasts- resorb alveolar bone
Odontoclasts resorb dentin and cememtum
Fibroclasts destroy collagen fibres of periodontal tissue