45. Aplasia, impacted, retentive teeth, persistant primary teeth.

Question 1

I. Aplasia
1/ Definition of aplasia

Answer 1

1. Anomaly in dentistry when the number of teeth is reduced
2. It is known as dental agenesis
3. Most common anomaly during tooth development
4. A result of poorly expressed ectoderm

Question 2

I. Aplasia
2/ Cause of Aplasia

Answer 2

Aplasia happens due to epigenetic and environmental reasons.

Question 3

I. Aplasia
3/ What are consequences of aplasia?

Answer 3

1. Malocclusion - imperfect positioning of the teeth when the jaws are closed.
2. Periodontal damage
3. Communication issues
4. Reduced chewing ability
5. Unfavorable appearance

Question 4

I. Aplasia
4. What happen after the primary tooth is missing?

Answer 4

There is a high chance that it’s permanent counterpart is missing

Question 4

I. Aplasia
4. What happen after the primary tooth is missing?

Answer 4

There is a high chance that it’s permanent counterpart is missing

Question 5

II. Impacted
1. What is the definition of impacted teeth?

Answer 5

development of the tooth is complete, BUT the tooth did not pass through the gum line due to obstacle. (usually – lower 3rd molar or canines)

Question 6

II. Impacted
2. What is the primary cause of impacted teeth?

Answer 6

tooth crowding / obstruction – can be treated surgically or orthodontically

Question 7

II. Impacted teeth
3. What are the possible complications of impacted teeth?

Answer 7

• resorption
• shifting

Question 8

III. Retained teeth
1. Definition of retained teeth

Answer 8

• the development of the tooth is complete or partial
• no obstacle
• tooth stays in place and does not erupt

Question 9

IV. Definition of partially erupted tooth

Answer 9

no completely surrounded by the bone

Question 10

V. Definition of Persistent primary teeth

Answer 10

1. Decidual teeth retained beyond the time for normal
2. Considered persistent if in place 12 months after the time to exfoliate

Question 11

VI. What are primary reasons of Persistent primary teeth?

Answer 11

• Absence of permanent counterpart
• Permanent counterpart is impacted
• Does not follow a normal eruption