In relation to Number of Teeth

1. DEVELOPMENTAL DISTURBANCES
OF TEETH-NUMBER
Presented by,
Deeksha Karkada
IV BDS
12D7839

2. • INTRODUCTION
• COMMON DEVELOPMENTAL
DISTURBANCES OF TEETH
• ANODONTIA
• HYPODONTIA
• HYPERDONTIA
• CONCLUSION
• REFERENCES

3. INTRODUCTION
Developmental disturbances may be in terms of
tooth eruption age, size, shape, number and
position.
These are more common in the permanent
dentition than in the deciduous dentition.
Heredity is believed to be the most frequent cause
of these developmental disturbances.

4. DEVELOPMENTAL ALTERATIONS OF
TEETH
ANODONTIA HYPODONTIA
HYPERDONTIA

5. MICRODONTIA

8. ANODONTIA
Anodontia refers to a total lack of tooth
development.
TRUE
ANODONTIA(congenital
absence of teeth)
TOTAL ANODONTIA PARTIAL ANODONTIA

9. INDUCED or FALSE ANODONTIA occurs as a result of extraction of all
teeth, PSEUDOANODONTIA is sometimes applied to multiple
unerupted teeth.
• All teeth are missing,involves
deciduous and permanent dentition
• Rare condition
• Associated syndrome:Hereditary
Ectodermal Dyplasia
TOTAL
ANODONTIA
• Involves one or more teeth.
• Maxillary lateral incisiors, maxillary
or mandibular 2nd premolars are
commonly missing,often bilaterally
• Familial tendancy is present
PARTIAL
ANODONTIA

10. HYPODONTIA
HYPODONTIA refers to the lack of development of
one or more teeth.
OLIGODONTIA is a subdivision of hypodontia.
OLIGODONTIA indicates the lack of development of
six or more teeth.
SYNDROMES ASSOCIATED WITH HYPODONTIA:
1. Ankyloglossia superior.
2. Crouzon
3. Down
4. Ectodermal dyplasia
5. Ehlers Danlos
6. Turner

11. Etiopathogenesis :
• Absence of dental lamina. Dental lamina is extremely
sensitive to external stimuli and damage before tooth
formation can result in hypodontia.
• Trauma, infection, radiation, therapeutic medications,
endocrine disturbances, intrauterine disturbances.
Clinical Features:
• A female predominance of approx. 1.5:1 is reported.
• Hypodontia is uncommon in deciduous dentition(<1%of
population);when present-involves mandibular incisors.
• Common in permanent dentition-third molars are commonly
affected(20-23%of population).
• 2nd premolars, lateral incisors are also affected.
• Associated positively with microdontia, reduces alveolar development,
increased freeway space and retained primary teeth

12. Sequelae associated with hypodontia
Abnormal spacing of teeth
Delayed tooth formation
Delayed deciduous tooth exfoliation
Late permanent tooth eruption

13. MANAGEMENT OF HYPODONTIA
• No treatment may be required for a single missing
tooth.
• Prosthetic replacement-for multiple missing teeth.
Therapeutic options include:
1. Traditional fixed prosthodontics
2. Resin bonded bridges.
3. Osseo integrated implants with associated
prosthetic crowns.
4. For children and young adults, a resin-bonded
bridge often is appropriate while waiting for full
dental maturation.

14. HYPERDONTIA
HYPERDONTIA is the development of an increased
number of teeth,and the additional teeth are termed
‘supernumerary’.
• Genetic control appears to exert a strong influence.
SYNDROMES ASSOCIATED WITH HYPERDONTIA:
1. Gardener
2. Cleidocranial dysplasia
3. Ehlers-Danlos
4. Tricho-rhino-pharyngeal
5. Down
6. Crouzon

15. ETIOPATHOGENESIS
• Development of excess dental lamina which presumably
leads to the formation of additional tooth germ.
CLINICAL FEATURES
Prevalence in Caucasians is 1-3%;sligtly higher rate in
Asian populations.
Approx. 76-86% of casessingle-tooth hyperdontia
12-23%two-tooth hyperdontia
<1% casesthree or more extra teeth.

16. Single-tooth hyperdontia:Occurs more frequently
in permanent dentition.
90% in maxilla; strong predilection for anterior
region.
Most common site: Maxillary incisor
region,maxillary and mandibular fourth
molars,premolars,canines and lateral incisors.
Supernumerary teeth are usually unilateral.
Non syndromic multiple supernumerary teeth
occrs frequently in mandible.
Examples have been reported in gingiva, maxillary
tuberosity,palate, maxillary sinus,sphenomaxillary
fissure,nasal cavity,in between orbit and brain.
Hyperdontia is positively correlated with
macrodontia and exhibits 2:1 male predominance.

17. Terms used to describe supernumerary
teeth:
A supernumerary tooth in the maxillary anterior
incisor region”Mesiodens”
An accessory fourth molar”Distomolar”or
“Distodens”.
A posterior supernumerary tooth situated
lingually or buccally to a molar
tooth”Paramolar”

18. • Normal teeth may erupt into an appropriate
position(e.g., a canine present between two
premolars). This pattern of abnormal eruption is
called “dental transposition”
• Such misplaced teeth have been confused with
supernumerary teeth. Teeth involved: maxillary
canines, 1st premolars.
• Accessory teeth may be present in
newborns(natal teeth) and those arising within
the first 30 days of life(neonatal teeth)

19. TREATMENT AND PROGNOSIS
• The presence of supernumerary tooth should be
suspected if there is a significant delay in the
eruption of a localized portion of the dentition.
• Early diagnosis and treatment are crucial in
minimal aesthetic and functional problems of
adjacent teeth.
• Standard of care is early removal of accessory
tooth.

20. CONSEQUQENCE OF LATE THERAPY:
Delayed eruption or resoption of adjacent teeth.
Displacement of the teeth associated with
crowding.
Malocclusion
Diastema formation
Subacute pericoronitis
Gingivitis
Periodontitis
Abscess formation
Development of odontogenic cysts and tumors.

21. Early diagnosis and treatment are often crucial in
minimizing aesthetic and functional problems of the
adjacent teeth. Reports have documented spontaneous
eruption of the adjacent dentition in 75% of the cases if
the supernumerary tooth is removed early.
In selected cases, clinical judgement may not dictate
surgical removal , or patient resistance to therapy may
be present. In these instances regular monitoring is
appropriate.
If mobility is not a problem and the teeth are stable , they
should be retained. Traumatic ulcerations of the adjacent
soft tissue(Riga-Fede disease)may occur during breast-
feeding but often can be resolved with appropriate
measures.

22. Textbook of Pedodontics - Shobha Tandon (2nd
Edition)
Oral and Maxillofacial Pathology-Neville ,
Damm ,Allen , Bouquot (2nd Edition)
Shafer’s Textbook of Oral Pathology(7th Edition)
Textbook of Pediatric
Dentistry-Nikhil Marwah
(3rd Edition)