Primary Tooth Morphology

Question 1

what is a gingival cyst?

Answer 1

build up of keratin

developmental problem

Question 2

what is a congenital epulis?

Answer 2

growth on mucosa on a newborn

Question 3

what are natal/neonatal teeth?

Answer 3

teeth that are visable when baby is first born

Question 4

what is an eruption cyst?

Answer 4

separation of teh dental follicle and crown of tooth leads to blood accumulating between the crown and gingiva

Question 5

what notation do we use for deciduous teeth?

Answer 5

FDI notation: 5(UR), 6(UL), 7(LL), 8(LR)

Question 6

when do teeth start to form?

Answer 6

week 5 of iul

Question 7

when does hard tissue formation start?

Answer 7

week 13 of iul

Question 8

how much of each deciduous tooth is calcified at birth?

6

Answer 8

central incisor: 1/2
lateral incisor: 1/3
canines: tip
first molars: 1/2
second molars: 1/3
first permanent molars: tip

Question 9

what is a theory behinf tooth eruption?

4

Answer 9

resorption of the overlaying hard tissue
cellular proliferation at the apex of tooth
localised change in blood/hydrostatic pressure
metabolic activity within the PDL

Question 10

how does resporption of the overlaying hard tissue occur?

Answer 10

enzymes in the dental follicle

Question 11

how is the dental follicle involved in tooth eruption?

Answer 11

activated to initiate osteclastic activity in the alveolar bone ahead of the tooth and clear a path for tooth eruption

once crestal bone is breached, follicle likely to play lesser role

Question 12

when is eruption of deciduous teeth complete?

Answer 12

2.5 - 3 years old

Question 13

what is the order of deciduous tooth eruption?

Answer 13

ABDCE / 12435

lower before upper except lateral incisors

Question 14

what are the second deciduous teeth to erupt and at what age?

Answer 14

lateral incisors 7-16 months

52, 62, 72, 82

Question 14

what are the first deciduous teeth to erupt and at what age?

Answer 14

central incisors 4-6 months

51, 61, 71, 81

Question 15

what are the third deciduous teeth to erupt and at what age?

Answer 15

first molar 13-19 months

54, 64, 74, 84

Question 16

what are the fourth deciduous teeth to erupt and at what age?

Answer 16

canine 16-22 months

53, 63, 73, 83

Question 17

what are the fifth deciduous teeth to erupt and at what age?

Answer 17

second molar 15-33 months

55, 65, 75, 85

Question 18

what are the differences between primary and permanent crowns?

3

Answer 18

primary molars are wider mesiodistally
primary molar crowns are more bulbous
primary teeth usually whiter

Question 19

what feature is present on an upper first molar?

Answer 19

prominent mesiobuccal tubercle

Question 20

what feature is present on a lower first molar?

Answer 20

prominent mesiobuccal tubercle

Question 21

what feature is present on a upper second molar?

Answer 21

transverse ridge

Question 22

what feature is present on a lower second molar?

Answer 22

3 buccal cusps

Question 23

what are the differences between primary and permanent roots?

2

Answer 23

primary teeth have narrower roots
roots of primary molars are longer, more slender adn flare apically

allows room for the developing permanent tooth crowns

Question 24

what are the differences between primary and permanent pulps?

2

Answer 24

primary pulp chambers are large in proportion to the crowns
pulp horns of primary teeth extend high occlusally so are close to the enamel

Question 25

what are the diferences between primary and permanent root canals?

1

Answer 25

primary roots canals are ribbon shaped with many interconnecting and accessory canals

clinically impossible to clean

Question 26

what are the differences in primary and permanent hard tissues?

2

Answer 26

primary have thinner coronal dentine
primary have consistently thinner enamel

Question 27

what are the differences in occlusal in primary and permanent teeth?

4

spacings

Answer 27

anterior spacing in primary dentition
anthropoid spacing: mesial to upper canine
primate spacing: distal to lower canine
leeway space: mesio-distal space occupied by primary molars

Question 28

how long does it take for the completion of a root formation?

Answer 28

after date of eruption, takes 3 years for the permanent tooth root to complete apexogenesis

Question 29

describe the eruption path of permanent incisors

Answer 29

permanent incisors develop palatal to primary incisors