Post on 07-May-2015
Developmental abnormalities
Islam Kassem
Level 7
ikassem@dr.com
• There are many developmental abnormalities that can affect the teeth and facial skeleton. In most cases, clinicians need little more than to be able to recognize these abnormalities
ikassem@dr.com
ikassem@dr.com
ikassem@dr.com
Classification of developmental abnormalities
1-Anomalies of the teeth
2-Skeletal anomalies.
ikassem@dr.com
Anomalies of the teeth
1-Number
2-Structure
3-Size
4-Shape
5-Position.
ikassem@dr.com
Anomalies of the teeth
1-Number
2-Structure
3-Size
4-Shape
5-Position.
ikassem@dr.com
1-Abnormalities in number
• Missing teeth
• Additional teeth (hyperdontia)
ikassem@dr.com
ikassem@dr.com
Missing teeth
• Localized anodontia or hypodontia — usually third molars, upper lateral incisors or second premolars.
• Anodontia or hypodontia associated with
systemic disease — e.g. Down's syndrome,
ectodermal dysplasia.
ikassem@dr.com
ikassem@dr.com
ectodermal dysplasia
ikassem@dr.com
Additional teeth (hyperdontia)
• Localized hyperdontia — Supernumerary teeth
— Supplemental teeth
• Hyperdontia associated with specific
syndromes, e.g. cleidocranial dysplasia,
Gardener's syndrome.
ikassem@dr.com
ikassem@dr.com
ikassem@dr.com
ikassem@dr.com
Cleidocranial dysplasia
ikassem@dr.com
Anomalies of the teeth
1-Number
2-Structure
3-Size
4-Shape
5-Position.
ikassem@dr.com
2-Abnormalities in structure
• Genetic defects
• Acquired defects
ikassem@dr.com
Genetic defects
• Amelogenesis imperfecta — Hypoplastic type
— Hypocalcified type
— Hypomature type
• Dentinogenesis imperfecta
• Shell teeth
• Regional odontodysplasia (ghost teeth)
• Dentinal dysplasia (rootless teeth).
ikassem@dr.com
ikassem@dr.com
Shell tooth
ikassem@dr.com
Acquired defects
• Turner teeth — enamel defects caused by infection from overlying deciduous predecessor • Congenital syphilis — enamel hypoplastic and altered in shape (see below) • Severe childhood fevers, e.g. measles — linear enamel defects Fluorosis — discolouration or pitting of the enamel • Discolouration — e.g. tetracycline staining.
ikassem@dr.com
Turner tooth
ikassem@dr.com
Anomalies of the teeth
1-Number
2-Structure
3-Size
4-Shape
5-Position.
ikassem@dr.com
3-Abnormalities in size
• Macrodontia — large teeth
• Microdontia — small teeth, including
rudimentary teeth.
ikassem@dr.com
Macrodontia
ikassem@dr.com
Microdontia
ikassem@dr.com
Anomalies of the teeth
1-Number
2-Structure
3-Size
4-Shape
5-Position.
ikassem@dr.com
4-Abnormalities in shape
• Anomalies affecting -whole teeth
• Anomalies affecting the crowns
• Anomalies affecting roots andlor pulp canals
ikassem@dr.com
Anomalies affecting -whole teeth
• Fusion — two teeth joined together from the fusion of adjacent tooth germs • Gemination — two teeth joined together but arising from a single tooth germ • Concrescence — two teeth joined together by cementum • Dens-in-dente (invaginated odontome) — in folding of the outer surface of a tooth into the interior usually in the cingulum pit region of maxillary lateral incisors.
ikassem@dr.com
Fusion
ikassem@dr.com
Gemination
ikassem@dr.com
Concrecence
ikassem@dr.com
Dens in dente
ikassem@dr.com
Anomalies affecting the crowns
• Extra cusps • Congenital syphilis — Hutchinson 's incisors — crowns small, screwdriver or barrel-shaped, and often notched — Moon's/mulberry molars — dome-shaped or modular • Tapering pointed incisors — ectodermal dysplasia.
ikassem@dr.com
Congenital syphilis
ikassem@dr.com
Tapering pointed incisors — ectodermal dysplasia.
ikassem@dr.com
Anomalies affecting roots and or pulp canals
• Number — additional roots, e.g. two-rooted incisors, three-rooted premolars or four-rooted molars • Morphology, including: — Bifid roots — Excessively curved roots — Dilaceration — sharp bend in the root direction — Taurodontism — short, stumpy roots and longitudinally enlarged pulp chambers Pulp stones — localized or associated with specific syndromes, e.g. Ehlers-Danlos (floppy joint syndrome).
ikassem@dr.com
Bifid lower Premolar
ikassem@dr.com
3 root lower molar
ikassem@dr.com
Dilaceration — sharp bend in the root direction
ikassem@dr.com
Taurodontism — short, stumpy roots and
longitudinally enlarged pulp chambers
ikassem@dr.com
Pulp stones
ikassem@dr.com
Odontomes
• Enameloma/enamel pearl • Cementoma (see fibro-cemento-osseousmesions in — Benign cementoblastoma (true cementoma) — Periapical cemento-osseous dysplasia — Focal cemento-osseous dysplasia — Florid cemento-osseous dysplasia (gigantiform cementoma) • Composite — Compound odontome — made up of one or more small tooth-like denticles — Complex odontome — complex mass of disorganized dental tissue.
ikassem@dr.com
Enemeloma
ikassem@dr.com
Compound odontoma
ikassem@dr.com
Complex odontoma
ikassem@dr.com
Anomalies of the teeth
1-Number
2-Structure
3-Size
4-Shape
5-Position.
ikassem@dr.com
5-Abnormalities in position
• Delayed eruption
• Other positional anomalies
ikassem@dr.com
Delayed eruption
• Local causes — Loss of space — Abnormal crypt position — especially 8/8 and 3/3 — Overcrowding — Additional teeth — Retention of deciduous predecessor — Dentigerous and eruption cysts • Systemic causes — Metabolic diseases, e.g. cretinism and rickets — Developmental disturbances, e.g. cleidocranial dysplasia — Hereditary conditions, e.g. gingival fibromatosis and cherubism.
ikassem@dr.com
Other positional anomalies
• Transposition two teeth occupying exchanged positions • Wandering teeth, movement of unerupted teeth for no apparent reason (distal drift) • Submersion, second deciduous molars apparently descend into the jaws. Since these teeth do not in fact submerge, but rather remain in their original position while the adjacent Other positional anomalies • Transposition, two teeth occupying exchanged positions • Wandering teeth, movement of unerupted teeth for no apparent reason (distal drift) • Submersion, second deciduous molars apparently descend into the jaws. Since these teeth do not in fact submerge, but rather remain in their original position while the adjacent
ikassem@dr.com
Submerged tooth infra occlusion
ikassem@dr.com
Transposition
ikassem@dr.com
Wandering 5
ikassem@dr.com
Skeletal anomalies
• Abnormalities of the mandible and/or maxilla
• Other rare developmental diseases and
syndromes.
ikassem@dr.com
Abnormalities of the mandible or maxilla
• Micrognathia
• Macrognathia (prognathism)
• Other mandibular anomalies
ikassem@dr.com
Micrognathia
• True micrognathia — usually caused by bilateral hypoplasia of the jaw or agenesis of the condyles
• Acquired micrognathia — usually caused by unilateral early ankylosis of the temporomandibular joint.
ikassem@dr.com
Micrognathia
ikassem@dr.com
Macrognathia (prognathism)
• Genetic
• Relative prognathism — mandibular/maxillary
disparity
• Acquired, e.g. acromegaly owing to excessive
growth hormone from a pituitary tumour.
ikassem@dr.com
Macrognathia
ikassem@dr.com
Other mandibular anomalies
• Condylar hypoplasia
• Condylar hyperplasia
• Bifid condyle
• Coronoid hyperplasia.
ikassem@dr.com
Condylar hyperplasia
ikassem@dr.com
Cleft lip and palate
• Cleft lip — Unilateral, with or without alveolar ridge — Bilateral, with or without alveolar ridge • Cleft palate — Bifid uvula — Soft palate only — Soft and hard palate • Clefts of lip and palate (combined defects) — Unilateral (left or right) — Cleft palate with bilateral cleft lip.
ikassem@dr.com
Alveolar cleft
ikassem@dr.com
Localized bone defects
• Exostoses
— Torus palatinus
— Torus mandibularis
• Idiopathic bone cavities (see Ch. 25)
— Stafne's bone cavity.
ikassem@dr.com
Eagle’s syndrome
ikassem@dr.com
Other rare developmental diseases and syndromes
• Cleidocranial dysplasia
• Gorlin's syndrome (nevoid basal cell
carcinoma syndrome)
• Eagle syndrome
• Crouzon syndrome (craniofacial dysostosis)
• Apert syndrome
• Mandibular facial dysostosis (Treacher Collins
syndrome).
ikassem@dr.com
Curzon's syndrome
ikassem@dr.com
Thank you
• You can get it form
• http://www.slideshare.net/islamkassem
ikassem@dr.com