Shedding and Replacement

Question 1

Where do the tooth germs of the canines and incisors develop?

Answer 1

On the LINGUAL side of their predecessors

Question 2

Where do the tooth germs of the permanent pre-molars develop?

Answer 2

Between the divergent roots of the corresponding deciduous molars

Question 3

Describe the eruption of the
- maxillar
-mandibular
molars (no deciduous predecessors).

Answer 3

• the permanent molars in the maxilla originally have their occlusal surfaces facing distally, and only swing into position once the jaw has sufficiently grown
• the permanent molars in the mandible originally have their axes inclined mesial, and again only become vertical when sufficient jaw growth has occurred

Question 4

What is the name of the structure that connect the dental follicle to the lamina propria in permanent tooth germs?

Answer 4

Gubernacular cord

Question 5

What is the name of the eruptive pathway for permanent teeth?

Answer 5

The gubernacular canal

Question 6

What is the gubernacular cord made from?

Answer 6

fibrous tissue, made from the remnants of the dental lamina

Question 7

What are the three categories of post-eruptive tooth movement, after it has reached it’s occlusal functional position in the oral cavity?

Answer 7

• movement to accommodate growing jaws
• movement to compensate for occlusal wear
• movement to accommodate for interproximal wear

Question 8

Define tooth eruption.

Answer 8

The process by which a tooth moves axially from it’s developmental position in the alveolar crypt (jaw) to it’s functional position in the oral cavity.