Disorders of tooth form

Question 1

Where is enamel derived from

Answer 1

Epithelial components

Question 2

Where are dentine and cementum derived from

Answer 2

Mesenchymal components

Question 3

What is dilaceration

Answer 3

Abnormal angulation or bend in the root

Question 4

What is dens invaginatus

Answer 4

Infolding of enamel into dentine. Infold represent stagnation sites for bacteria and can predispose to caries

Question 5

What is dens evaginatus

Answer 5

Anomalous tubercule or cusp located towards the centre of the occlusal surface

Question 6

What is turner tooth

Answer 6

A tooth with an area of hypoplasia consequent to a periapical infection of its deciduous predecessor

Question 7

Hutchinson’s incisor

Answer 7

Peg shaped incisors caused by in- utero infection by congenital syphilis (Treponema pallidum)

Question 8

What is hypodontia/ partial anodontia

Answer 8

Less than 6 teeth missing

Question 9

What is anodontia

Answer 9

Congential absence of all primary or permanent teeth

Question 10

What is microdontia

Answer 10

Having smaller teeth than regular

Question 11

What is endogenous staining

Answer 11

Fluorosis

Affects the teeth whilst they are still developing

Question 12

What is exogenous staining

Answer 12

Tetracycline staining

Affects the teeth after eruption. Binds to calcium. Severity depends on dose, length of usage etc

Question 13

What is tetracycline

Answer 13

Antibiotic - used to treat bacterial infections

Question 14

What are ectodermal dysplasia’s

Answer 14

Diverse group of genetic disorders that involve defects of the hair, skin, nails

Question 15

What does hypohidrotic mean

Answer 15

Reduced ability to sweat.

Question 16

What does hyptrichotic mean

Answer 16

Reduced hair

Question 17

How many forms of amelogenesis are there

Answer 17

14

Question 18

How is amelogenesis characterised

Answer 18

Enamel hypoplasia/ hypomineralisation

Question 19

What inheritance pattern is amelogenesis

Answer 19

X linked recessive

Question 20

What are the classifications of amelogenesis

Answer 20

Class I - Hypoplastic
Class II - Hypomaturation
Class III - Hypocalcified
Class IV - Hypomaturation with taurodontism

Question 21

What is taurodontism

Answer 21

Anomaly defined by enlargement of the pulp chamber

Question 22

How many types of dentinogenesis are there

Answer 22

3

Question 23

What are the different types of dentinogenesis

Answer 23

Type I DI - Occurs in people who also have osteogenesis imperfecta. This condition is similar in genetic origin but causes brittle bones.
Type II DI occurs in people without another hereditary disorder and affects primary more than permanent teeth. This may occur in people who exhibit signs of age-related hearing loss or deafness. Type II is the most common type of dentinogenesis imperfecta.
ACCORDING TO THE NATIONAL ORGANIZATION FOR RARE DISORDERS, type III DI occurs in people without another hereditary disorder and seems to be isolated to a group of individuals in southern Maryland.