School of
Developmental Abnormalities
of Teeth
Zhang Qi
Wuhan University School of
Stomatology
School of
Classification
?Anomalies of Number
?Anomalies of Size
?Anomalies of Shape
?Anomalies of Structure
?Anomalies of Color
School of
Anomalies of Number
1,Anodontia,a complete absence of
one or both dentition.
2,Hypodontia (partial anodontia):
a deficiency in tooth number.
3,Hyperdontia (Supernumerary Teeth):
an excess in tooth number,
a,Mesiodens b,Distomolar
School of
Mesiodens
School of
Anomalies of Size
1,Microdontia
2,Macrodontia
School of
Anomalies of Shape
1,Gemination
2,Fusion
3,Concrescence
4,Dilaceration
5,Enamel Pearl (enameloma)
6,Talon Cusp
7,Taurodontism
8,Dens in Dente (dens invaginatus)
9,Dens Evaginatus
10.Supernumerary Roots
11.Hypercementosis
School of
Gemination
The partial development of two teeth
from a single tooth bud following
incomplete division.
An incomplete division of a single
tooth bud resulting in a bifid crown
with a single pulp chamber.
School of
Gemination
School of
The dentinal union of two embryologically
developing teeth.
Fused teeth can contain two separate
pulp chamber,may appear as large bifid
crowns with one chamber.
Fusion
School of
Fusion
School of
An acquired disorder in which the roots of
one or more teeth are united by cementun
alone after formation of the crowns.
Concrescence
School of
Concrescence
School of
GEMINATION FUSION CONCRESCENCE
One bud
One tooth
One canal
Two buds
Two teeth
Dentin union
Two buds
Two teeth
Cementum union
School of
An extra cusp,usually in the central
groove or ridge of a posterior tooth
and lateral incisor,
Dens Invaginatus
School of
A condition resulting from the
invagination of the inner enamel
epithelium producing the appearance
of a tooth within a tooth,
Dens in Dente
School of
Dens in Dente
(dens invaginatus)
School of
Taurodont teeth are characterized by
having a significantly elongated pulp
chamber with short stunted roots,
resulting from the failure of the proper
level of horizontal invagination of
Hertwig’s epithelial root sheath.,
Taurodont
School of
Taurodontism-bull like tooth
School of
Dilaceration refers to an abnormal
bend of the root during its development
and is thought to result from a traumatic
Episode.
Dilaceration
School of
School of
Anomalies of Structure
1,Enamel hypoplasia caused by
amelogenesis imperfecta (genetic)
2,Enamel Hypoplasia caused by
febrile Illness or Vitamin Deficiency
3,Enamel hypoplasia resulting from
local infection or Trauma
a,Turner's Tooth
4,Enamel hypoplasia resulting from
fluoride Ingestion (dental fluorosis)
a,Mottling
School of
Anomalies of Structure
5,Enamel hypoplasia resulting from
congenital syphilis (Treponema pallidum)
a,Hutchinson's incisors b,Mulberry molars
6,Enamel hypoplasia resulting from birth injury,
premature birth or idiopathic factors
7,Enamel hypocalcification
8,Dentinogenesis imperfecta
9,Dentin dysplasia
10,Regional Odontodysplasia (Ghost teeth)
School of
Classification of AI
Type I,hypoplastic
TypeII,hypomaturation
TypeIII,hypocalcified
TypeIV,hypomaturation-hypoplastic
with taurodontism
Amelogenesis Imperfecta
School of
Amelogenesis imperfecta
School of
enamel hypoplasia
School of
enamel hypoplasia
School of
Turner Tooth
School of
Dental fluorosis
School of
Hutchinson teeth
School of
Classification of DI
Type I,occures with osteogenesis
imperfecta
TypeII,hereditary opalescent dentin
TypeIII,Brandywine type
a shell-like appearance and
multipe pulp exposures.
Dentinogenesis Imperfecta
School of
Dentinogenesis imperfecta
School of
School of
Anomalies of Color
— Discoloration of teeth
Etiology
?Surface deposits (Extrinsic stains)
?Changes in structure or thickness of dental tissues
?Diffusion of pigments into dental tissues
?Pigments incorporated during formation of dental tissues.
School of
Extrinsic stains
? Substances in the diet
? Habitual chewing,betel nut,tobacco
?Tobacco smoking
? Medicaments
? Chromogenic bacteria
School of
Changes in structure
? Enamel hypoplasias,fluorosis
?Amelogenesis imperfecta,hypocalcified,
hypomaturation,and hypoplastic types
? Enamel opacities
? Enamel caries
? Dentinogenesis imperfecta
? age changes in dental tissues
School of
Diffusion of pigments
? Extrinsic stains
? Endodontic materials
? Products of pulp necrosis
School of
Pigments incorporation
? Bile pigments
? Porphyrins
?Tetracycline
School of
Tetracycline stained teeth
School of
School of
School of
Composite resin restoration
School of
School of
Other disorders of teeth
School of
Attrition
School of
Erosion
School of
Toothbrush abrasion