Radiographic assessment of developmental anomalies of teeth

1. Developmental
Anomalies
of teeth

2. M.Ekram
Chapter 18
White & Pharoh
Page 330
Reference:

3. M.Ekram
Causes of Developmental Anomalies
1. Genetic: inherited or gene mutation.
2. Environmental causes:
Infection, trauma, radiation.
hormonal disturbances.
nutritional deficiencies.
hypoxia
miscellaneous

4. M.Ekram
Classification
Size Shape Number Structure
Disturbance
in eruption
Microdontia
macrodontia
gemination,
fusion.
Concrescence.
Dilaceration.
Talon cusp.
dense-in-dent.
Dens
invaginatus
Taurodontism.
Missing teeth
supernumerary
Amelogenesis
dentinogenisis
imperfecta.
Dentin
dysplasia
Trasposition
premature
delayed
eruption

5. M.Ekram
Anomalies in tooth size
Microdontia
True:
Generalized → all teeth.
e.g. in dwarfism
Single, group of teeth → #2 (peg shape )
→ # 8 (fused roots)
Relative Microdontia: as normal sized teeth in
large mandible
Clinically: identified easily

6. M.Ekram
Radiographically:
small sized crown and root
Microdontia (cont.)

7. M.Ekram
Macrodontia
True
generalized Localized
all teeth in facial hemi-
in Gigantism hypertrophy
clinically: single macrodont is
difficult to be identified from
gemination or fusion
Relative
normal or slightly
large teeth in small
jaw

8. M.Ekram
Developmental Anomalies in
Teeth Number
Increased number
supernumerary teeth.
Predeciduous dent.
Post permanent dent.
Decreased number
Hypodontia
Oligodontia
Anodontia.
partial-
anodontia

9. M.Ekram
Supernumerary Teeth
Arise from extra-teeth buds.
Rare in deciduous teeth.
May resemble the tooth anatomically or
not.

10. M.Ekram
Supernumerary Teeth
Sites
any where, But the most
common are:
Mesiodense: between
#1,#1. Small, conical
inverted, impacted,
short root.
Paramolars: located
around the premolar-
molars.

11. M.Ekram
Supernumerary Teeth
Distomolar: Distal to # 8,
small, rudimentary.

12. M.Ekram
Clinical Picture
May prevent eruption or displacement of normal teeth
or cause tooth resorption.
Multiple Supernumerary Teeth Are manifested in :
1. Gardner’s Syndrome: multiple supernumerary and
impacted teeth, multiple polyps of large
intestine,multiple osteomas , sebaceous cysts.

13. M.Ekram
Abnormalities
Bifid ribs and other skeletal abnormalities.
Multiple jaw cysts.
Multiple nevoid basal cell carcinomas.
Characteristic frontal
bossing and broad
nasal root
Bifid ribs Multiple cyst - like radiolucencies
1. Gorlin-Goltz Syndrome: (basal cell nevous-
bifid rib syndrome).

14. M.Ekram
3. Cleido-cranial dysostosis: large skull with
mental retardation, open fontanells, small
maxilla, high arched palate, absent or
hypoplastic clavicles.

15. M.Ekram
Predeciduous Dentition
Hornified structure at birth
or just after.
Due to extra-teeth buds.
Most common in lower
anterior area.
Present just above the
alveolar ridge, so easily
removed.
NB: we should differentiate
between it and deciduous
teeth before attempting
removal.

16. M.Ekram
Post-permanent Dentition
Third Dentition
After extraction of all teeth and
construction of denture, new teeth
begin to erupt.
They may be either impacted.
Or supernumerary unerupted teeth.

17. M.Ekram

18. M.Ekram

19. M.Ekram
Decrease Number of Teeth
Missing teeth - Anodontia
Total Anodontia:
failure of odontogenesis
rare but may accompany:
H. Ectodermal Dysplasia:
with dry skin, absence of
sweet glands, scanty hair,
patient can not tolerate
heat.
Partial Anodontia:
few teeth: Hypodontia
Many teeth: Oligodontia.
More common than total A.
Frequency:
#8 > #2 >#5 in permanent.
Upper # B > lower # B

20. M.Ekram
Hereditary
Radiation to the head in a very early stage of
development with either a total destruction of
teeth buds, or the teeth are partially developed
and hypo-calcified with stunted growth.
Diagnosis:
proper history and exclusion of extraction help
in diagnosis. Then radiographic examination
confirms the clinical ex.
Etiology (Anodontia)

21. M.Ekram
Anodontia

22. M.Ekram
Ectodermal dysplasia
Fine scanty hairs Anodontia

23. M.Ekram
Anodontia

24. M.Ekram
Ectodermal dysplasia

25. M.Ekram
Anomalies in eruption of teeth
Transposition
1. Permanent canine and 1st premolar.
2. Second premolar (between 6 & 7).
3. Central & lateral incisors.
N.B. Transposition was not reported in Pry teeth but may be
with hypodontia or supernumerary teeth.
Teeth commonly involved

26. M.Ekram
Anomalies in tooth Shape
Gemination (twinning)
Partial division
tooth with a single root and
a crown that is divided
totally or partially.
Complete division
complete separation with
formation of 2 teeth with
crowns and roots.
N.B. the result is a normal teeth
No + supernumerary tooth.
A single tooth bud divides by an
invagination

27. M.Ekram
Complete
separationPartial division

28. M.Ekram
Clinical Picture of Gemination
Site:
anterior (deciduous or
permanent).
Structure:
enamel and dentin may
be hypoplastic or
hypocalcified.

29. M.Ekram
Radiographic Picture of Gemination
Large tooth with well
defined enamel
separating the two
parts.
One large pulp
chamber or partially
divided one.

30. M.Ekram
Gemination
Divided pulp chamber One pulp chamber

31. M.Ekram
Clinical implications of Gemination
Poor esthetics due to a partially divided tooth.
Hypoplastic enamel and increased caries
susceptibility
Malocclusion and periodontal problems.

32. M.Ekram
Fusion
Union of two normally separated teeth.
Theories and types
1- fusion occurs early before
calcification:
the tooth formed is one single large
tooth.
2- fusion occurs late after
calcification:
there may be union in the roots only
with two separate or single root canal.

33. M.Ekram
Clinical Picture of Fusion
Decreased number of
teeth by one.
Occurs more in
deciduous teeth.
More in anterior.
The crown may be
bifid

34. M.Ekram
What happens when fusion occurs between
normal tooth and supernumerary tooth ?
it will be very difficult to be differentiated
from gemination !!!!!

35. M.Ekram
Radiographic picture of fusion
Single root with cleft crown
(fusion occurs late after calcification had started)

36. M.Ekram
fusion
Fusion In deciduous teeth
2 separate root canals

37. M.Ekram
Differences between
fusion and gemination
Fusion
Number of teeth is less by
one except if fusion
occurs with extra-tooth.
Tooth with 2 separate
Root Canals with one or
two roots.
Gemination
Number of teeth is
correct or increased by
one.
Tooth with large pulp
chamber with either
clefted or partially
divided crown.
N.B. Also from macrodontia

38. M.Ekram

39. M.Ekram
Concrescence
It is a form of fusion but by cementum
only.
Etiology
trauma and crowding of teeth
with resorption of interdental bone
so that teeth are united with
deposition of cementum.
It may occur before or after
development of teeth (true &
acquired).
Significance: during teeth extraction.

40. M.Ekram
Taurodontism
Describes the increase in
length of the crown on the
expense of root with
elongated pulp chamber
so, it shows increase
distance between the
CEJ and root furcation.
The name derived from similarity of teeth to that of
Cud-chewing animals, so termed Bull-like teeth.

41. M.Ekram
Etiology: mutation resulting from odotoblastic
deficiency during formation of roots.
Clinically : indistinguishable

42. M.Ekram
Radiographic features
1.tooth rectangular in shape.
2. Large elongated pulp chamber.
3. Lack of usual constriction at cervical area.
4. Furcation is few mms away from the apex (short root).

43. M.Ekram
Dilaceration
This term refers to an angle or sharp
bend either in the crown or root.
Etiology: Developmental or could be due to
trauma
Trauma of deciduous teeth may cause
dilaceration of the permanents.
Clinically
Site: any where in the root and may be in
the crown.
More in maxillary anterior teeth.

44. M.Ekram
Clinical and Radiographic Picture
(Dilaceration)
Teeth may not erupt.
If in the crown: bad
esthetics.
If in the root: has no
significance except in
endodontics and
extraction.
Radiographically
appears if dilaceration is to the mesial or distal.
Appears as well defined RO area with LD in the center
(apical foramen) giving the appearance of “bulls’ eye”

45. M.Ekram
Dilaceration
Buccal or lingual dilaceration
Distal dilacerationDistal dilaceration
Clear angulation

46. M.Ekram
Differential Diagnosis of Dilaceration
some times it is difficult to be differentiated from
condensing osteitis,
idiopathic osteosclerosis.
fused roots.
N.B. we take radiographs from different angles

47. M.Ekram
Dense-in-Dent
It is due to enfolding of the
enamel organ to the
interior during
development and before
calcification.
Etiology:
1- focal growth stimulation
or focal growth
retardation in certain
areas.
2- External trauma.

48. M.Ekram
Clinical Picture of Dens-in-Dent
Incidence: tooth #2> #1
Site: most common in crowns, but may be in the roots
due to folding of epithelial root sheath of Hertwing.
It Appears as a palatal pit.
N.B. the most extreme form of this anomaly is referred to
as Dilated odontome.

49. M.Ekram
Clinical Picture of Dens-in-Dent
Clinical significance:
 The palatal pit is difficult to
clean.
very thin enamel separate
the defect from the pulp
chamber.
There is a risk of caries
and pulp necrosis.

50. M.Ekram
Coronally
pear-shaped area of enamel and
dentin.
Narrow constriction at the
opening .
Closely approximated to the pulp
in depth.
Radiographic Picture of Dens-in-Dent

51. M.Ekram
Radicular
lined with cementum,
may reach to the apical
foramen (not as defined
as the coronally).
Radiographic Picture of Dens-in-Dent

52. M.Ekram
Dense-in-Dent
Reported Case

53. M.Ekram
Dense evaginatus
Leong’s premolar
Clinically:
Occurs in premolars, as
a tubercle of enamel in
the middle of the
occlusal surface.
covered with enamel
and composed of
dentin and a core of
pulp.
It is due to out folding
of the enamel organ.

54. M.Ekram
Dense evaginatus
Radiographically: extension of pulp covered by
E & D.
Significance:
occlusal interference.
prevention of complete eruption of the
opposing tooth.
wearing with subsequently pulp exposure.

55. M.Ekram
Talon Cusp
It is projecting from the cingulum of
upper or lower anterior teeth.
Clinical Picture
Surrounded by 2 grooves.
Blends to the surface of the
tooth.
Significance
* May Interfere with occlusion.
* Caries susceptibility

56. M.Ekram
Radiographic picture of Talon Cusp
Differential diagnosis : Supernumerary teeth (buccal
object rule).

57. M.Ekram
Enamel Pearl
Is a small globule of enamel1-3 mm
in diameter that occurs on the roots
of molars (furcation area).
DD
1. Isolated piece of calculus
2. Pulp stone (buccal object rule –
vertically).

58. Anomalies in Tooth
Structure

59. M.Ekram
Developmental anomaly that affects enamel
formation.
Marked changes in E in either part or all the
teeth in both dentitions.
Dentin and roots are usually normal.
Causes delayed eruption of the affected teeth.
Increases tendency for impaction.
Amelogenesis Imperfecta (AI)

60. M.Ekram
AI: Types
E. Hypoplastic type. in matrix formation.
E. Hypocalcification in mineralization.
E. Hypomaturation.
Hypomaturation. Hypocalcifid type. (mottled E).

61. M.Ekram
Clinical Picture (AI)
Hypoplastic type
Thin enamel & dentin is
shown, so the teeth are
dark or brown in color.
Loss of normal tooth
contour and teeth become
undersized.
Lack of proximal contact.
Occlusal surfaces are
usually flat (attrition).

62. M.Ekram
E Hypomaturation type
Clinical features
Enamel is of normal thickness but mottled.
Enamel can be pierced by probe.
Patient may be affected by different degrees.
Teeth may show vertical grooves.
Teeth may be chalky or dark in color.
radiographically.
Enamel is of normal thickness but with density
similar to D.

63. M.Ekram
Clinical picture (AI)
E Hypocalcification type
Clinical features
Staining of the tooth
occurs due to increased
permeability.
Associated with deposition of secondary
dentine in the pulp. Therefore ,
resembles DI
Staining of the tooth
occurs due to increased permeability.

64. M.Ekram
E Hypocalcification
Normal enamel thickness with less density than D.
Radiographically.

65. M.Ekram
Radiographically
The diagnosis depends mainly
on the clinical examination.
The teeth are Normal or Square-
shaped with thin opaque mottled E .
(according to the thickness of enamel).
Enamel may be lost and very difficult
to differentiate it from DI.

66. M.Ekram
DD of AI
From DI why ?
If formation of secondary dentin with
obliteration of the pulp is associated with
Enamel abrasion, this will resemble DI.
However bulbous tooth + obliterated short
roots rule out AI.

67. M.Ekram
Dentinogenesis imperfecta (DI)
It is a developmental anomaly affecting dentin in both
sexes and both dentitions.
Hereditary opalescent dentin

68. M.Ekram
Type I Type II
usually + O I Never with O I
Unless by chance
Types of Dentinogenesis imperfecta
(DI)

69. M.Ekram
General clinical picture (D I)
Type I: more in deciduous teeth > permanent
Type II: equal in both
Tooth Color:
Teeth vary in color from
brownish, yellowish brown
or to even violet with
unusual translucency.
Enamel:
May be lost due to
abnormal DEJ, so dentin
undergo discoloration and
rapid attrition.
opalescent dentin

70. M.Ekram
Radiographic Picture (DI)
Bulbous teeth with variable degrees
of attrition.
In the early stage of development, the
pulp appears more wide then quickly
shows calcification.
Partial or total obliteration of pulp due
to deposition of dentin in both
deciduous and permanent teeth.
Short blunted roots.
Occasionally associated with
multiple periapical R L. without
actual pulp exposure but not as
frequent as in D dysplasia.

71. M.Ekram
Radiographic Picture (DI)

72. M.Ekram
Osteogenesis imperfecta
Hereditary disorder
Clinical features
Skeletal deformities
Blue sclera
Progressive osteopenia
Class III malocclusion
Impacted 1st & 2nd molars.
Dentinogenesis imperfecta
(25% of cases)

73. M.Ekram
Dentin Dysplasia
(Rootless teeth)
Very rare, characterized by normal E,
defective D, abnormal pulp
morphology.
Very short conical roots with
obliteration of pulp.
Associated with periapical RL.

74. M.Ekram
Rootless Teeth

75. M.Ekram
Dentin Dysplasia: Types
Type I (Radicular)
Roots are either short or of
abnormal shape (specules).
Obliteration of pulp before
eruption.
Associated with periapical
radiolucencies.
Teeth of normal color
Teeth malalignment
Tooth exfoliation
Type II (Coronal)
Crowns as in DI
Obliteration of pulp after
eruption
Pulp chambers may
become flame-like shaped.
Anterior teeth and
premolars may develop
thistle-tube shaped pulp
chamber.

76. M.Ekram
Rootless Teeth Type I

77. M.Ekram
Rootless Teeth Type II
Flame-like pulp chamber Thistle-like pulp

78. M.Ekram
DD of Dentin Dysplasia
D Imperfecta
Crown: bulbous bell-
shaped
Root: short
Obliterated pulp chamber
D Dysplasia
Crown: Normal size and
shape.
Root: short or normal
Type II shows obliteration
after eruption
Pulp chamber is thistle-
tube- shaped or flame-like.
Rarifying osteitis is more
frequent.
Both causes discoloration of teeth and obliteration
of pulp chamber.

79. M.Ekram
Regional Odontodysplasia
(Ghost teeth)
It is a relatively rare disorder of unknown
etiology affecting both E & D of both
dentitions.
E and D are both hypoplastic and
hypocalcified.
Results in arresting development of the
involved teeth.
One or several teeth in a localized area are
affected.

80. M.Ekram
Ghost tooth
Clinically:
It affects maxillary anterior
teeth more than mandibular.
Central > lateral > canine.
Teeth have irregular shape
with defective mineralization.
Teeth show delayed eruption.
Increase incidence of caries,
pulp infection and tooth
fracture.

81. M.Ekram
Ghost tooth
Radiographically
thin E & D with large
pulp.
Sometimes E is very
hypo-dens so that it may
not be evident on
radiographs.

82. M.Ekram
DD of Odontodysplasia
D Imperfecta
Family history
E is normal
Involves all teeth
Odontodysplasia
No family history
E is hypoplastic
Few or group of teeth
in the arch are only
affected.
It may resemble DI But:

83. M.Ekram
Turner’s Hypoplasia
Usually involve single tooth.
Permanent > deciduous.
Ranges from mild discoloration or pitting of E,
to severe defects and abnormal anatomy.
Due to infection or trauma to deciduous.

84. M.Ekram
Congenital Syphilis
Affects permanent
dentition more than
deciduous.
Deciduous teeth are
usually normal as
abortion would occur if
treponeamal spirocheats
get access through the
placenta to the fetus.

85. M.Ekram
Clinical features
Anterior teeth : Hutchinson’s
teeth.
#1 >#2 >#6
Screw driver with rounding of
the mesial and distal incisal
angles.
Notching of the incisal edge.
Molars: Mulberry molars or
Moon's molars
narrow crown with globular
shaped cusps.
E. hypoplasia due to syphilis has a very
pathognomonic features.

86. M.Ekram
Thank you
Questions ?