Developmental Anomalies of teeth

Question 1

What are the Normal criteria of teeth

Answer 1

Normal no.=1ry →20 teeth
▪ Permenant→32 teeth
▪ Number of roots
▪ Shape and form of crowns and roots..
▪ Size of teeth
▪ tooth composition of enamel and dentine
▪ Time of shedding and eruptio

Question 2

Define Anodontia.

Answer 2

Total failure of development of a complete
dentition .
Very rare.

Question 3

Define Hypodontia (Isolated Oligodontia

Answer 3

Failure of development of one or two teeth
-is hereditary.
-Most common affected teeth:
3rd molars,2nd mandibular molars
maxillary
lateral incisors then the maxillary 2nd premolar

Question 4

How does Oligodontia differ from Hypodontia?
And andontia

Answer 4

Oligodontia is the absence of more than 6 teeth 15% 2-10
Hypodontia is the absence of one or two teeth except 3 molar 1%
Andontia is the absence of all teeth

Question 5

Define a syndrome

Answer 5

group of( unrelated) signs and symptoms that together are characteristic of a specific disorder

Question 6

What syndrome is associated with oligodontia or anodontia and systemic defects and characteristics

Answer 6

Anhidrotic (hereditary) ectodermal
dysplasia

Usually a sex-linked recessive trait
• Hypodontia
• Hypotrichosis (scanty hair)
• Anhidrosis (inability to sweat)→fever +soft ,
dry, smooth ski

Question 7

( Hyperdontia )Additional teeth
Define Supernumerary teeth
Shape
Site

Answer 7

• 1Supernumerary teeth = any additional tooth
  Shaped: Conical or more seriously malformed
  Site: the incisor or molar region.
  Mostly in the midline is called Mesiodens

Question 8

Define Supplemental teeth
Shape

Answer 8

These are supernumerary
teeth with normal morphology,

Question 9

What is a Paradental tooth?
And Distomolar
موقع الاسنان اللي بتطلع فين

Answer 9

A posterior tooth situated buccally or lingually to a molar

accessory fourth molar

Question 10

Define Natal teeth and
Neonatal teeth
And types of teeth

Answer 10

Teeth present above the gum line at birth

Teeth present during the first month of life

baby’s normal deciduous or
could be supernumerary teeth

Question 11

What is the general rule for managing natal teeth?

Answer 11

The tooth should be maintained until it is necessary to be removed, as it may be attached to a permanent tooth bud

Question 12

What is the first step if extraction of a natal tooth is decided

Answer 12

Take an X-ray to determine if it is supernumerary or not.

Question 13

When is it safer to extract a natal tooth?

Answer 13

2-it is safer to wait until a child is 10 days old. Until the
commensal flora of the intestine is
produces vitamin K →essential for the production of
prothrombin in the liver to avoid hemorrhage for the
infant

Question 14

What are characteristics of Cleidocranial dysplasia syndrome

Answer 14

Teeth:
Baby teeth that do not come out on their own
• Impacted adult teeth
• Supernumerary (extra) teeth
• Crowded teeth
• Malocclusion
• Thin tooth enamel, more prone to caries
Skull and Face:
• High-arched hard palate or cleft palate
Other: • Incompletely formed or missing clavicles

Question 15

What are the main features of Gardner Syndrome

Answer 15

• hereditary intestinal polyposis
• supernumerary teeth,

Question 16

Define Macrodontia.
And type

Answer 16

Enlargement of the dentition
Type:
Isolated: Hemifacial hypertrophy(Third molars)
generalized:
relative(false)
true بسبب pituitary gigantism تضخم

Question 17

Define Microdontia.
What are examples of Isolated and generalized microdontia

Answer 17

Abnormally small teeth.

A-isolated: peg shaped lateral or maxillary 3rd molars.
B-generalized:→ true–pituitary dwarfism ضمور الغدة or down syndrome
→relative(false) with macrognathia تضخم الفك

Question 18

Define Dilaceration.

Answer 18

abnormal curvatur of the root due to trauma
during developmentانحناء

Question 19

Define Taurodontism( bull teeth)
المتلازمه

Answer 19

in down syndrome& eskimos
An enlarged pulp chamber, apical
displacement of the pulpal floor

Question 20

Dens invaginatus(dense in
dente
التعريف
المكان

Answer 20

is a developmental malformation, in which there is an
infolding of enamel into dentine
Moslty in max laterlas + canine.

Question 21

Dense Evaginatus تعريف

Answer 21

developmental anomaly that is found in teeth where the outer
surface appears to form an extra bump or cusp

Question 22

What syndrome is a Talon cusp mainly found in?
والتعريف

Answer 22

(rubinstein taybi syndrome)

rare dental anomaly resulting in an extra cusp or cusp-like projection
on an anterior tooth, located on the inside surface of the affected tooth

Question 23

Supernumerary root
مكانه

Answer 23

-mostly in mand.canines,PM &molar

Question 24

Gemination التعريف
عدد الاسنان في الفك

Answer 24

dental phenomenon that appears to be two teeth developed from one.
there’s is one main crown with a cleft in it that, within the incisal third of the crown,
the number of the teeth in the arch will be normal

Question 25

Fusion التعريف

Answer 25

The Union of two normally separated teeth germs, may be complete or incomplete. union of a normal tooth bud to a supernumerary tooth germ. The number of teeth is fewer if the anomalous tooth is counted as one tooth Fusion can occur in deciduous or permanent teeth .its more common in anterior teeth depending on the stage of odontogenesis

Question 26

Concresence

Answer 26

the cementum overlying the roots of at least two teeth fuse together without the involvement of denti

Question 27

Enameloma=Enamel drop=Enamel pearl تعريف اسباب

Answer 27

is a small white mass of ectopic enamel attached to a root surface near the cementoenamel junction (CEJ due to presence of epithelial root sheath of hertwig

Question 28

Ankylosis تعريف

Answer 28

Ankylosis =bone +tooth Ankylosis occurs when partial root resorption is followed by repair with either cementum or dentine that unites the tooth root with the alveolar bone

Question 29

Hypercementosis

Answer 29

excessive deposition of cementum on the tooth root

Question 30

What are the main etiologic factors for enamel defects

Answer 30

1-Environmental(acquired): A local (Turner’s ) B-systemic -Fluorosis: -Birth trauma -infectious childhood disease -nutritional defect (rickets) -congenital syphilis Amelogenesis imperfecta 2

Question 31

Turner’s teeth تعريف

Answer 31

enamel hypoplastic defect in the permanent teeth caused by periapical inflammatory disease in the overlying primary tooth

Question 32

Congenital syphilis تعريف وبتظهر مع اي

Answer 32

Congenital syphilis may present with Hutchinson teeth (notched, peg-shaped upper central incisors) and mulberry molars. The Hutchinson triad— Hutchinson teeth, interstitial keratitis, and sensorineural hearing loss—is relatively specific for this conditin.

Question 33

What is the Neonatal Line and why is it important?

Answer 33

•Neonatal Line: A dark, wide line in enamel due to birth stress (from intrauterine to extrauterine life). •Seen in: All primary teeth + first permanent molars (mandibular + maxillary). •Appearance: Darker and thicker than other striae of Retzius (~16 μm). ❖In forensic dentistry,طب شرعي •Importance: Distinguishes prenatal from postnatal enamel formation.

Question 34

Amelogenesis imperfecta تعريف

Answer 34

is a disorder of tooth development. This condition causes teeth to be unusually small , discolored, pitted or grooved, and prone to rapid wear and breakag

Question 35

Hereditary opalescent(blue) dentine =Dentinogenesis imperfecta

Answer 35

This condition causes the teeth to be discolored (most often a blue-gray or yellow- brown color) and translucent. Teeth are also weaker than normal, making them prone to rapid wear, breakage, and loss. Associated with blue sclera

Question 36

Dentinogenesis imperfecta (bell or tulip teeth

Answer 36

Crown shape: Bulbous crowns with cervical constriction (“bell” or “tulip” teeth). • Color: Amber translucent discoloration.كهرماني • Tooth quality: Weak with rapid attrition. • Roots: Short and constricted. • Pulp: Pulp obliteration is common. • Teeth affected: Both primary and permanent.