Dental%20Anomalies%20in%20Radiology

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Dental Anomalies in Radiology
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• Developmental abnormalities v.s. acquired
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• Ref 1 White SC, Pharoah MJ. Oral Radiology
• Principles and interpretation 6th ed. 2009.
• Ref 2 Neville BW, Damm DD, Allen CM and Bouquot
  JE. Oral maxillofacial patholgy 3nd ed. 2009.
• Ref 3????????????

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Supernumerary Teeth (hyperdontia, supplemental
teeth)
Developmental Abnormalities

• 14 , familial tendency
• Mesiodens, paramolar
• Distodens, distomolar teeth
• Peridens
• Single premaxilla, maxillary molar
• Multiple premolar area, mandibular
  
• M F 2 1
• Impaction or delay eruption of normal teeth
  dentigerous cyst
• Syndrome
• Cleidocranial dysplasia, Gardners syn.

Ref.1
4
Ref.3
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Cleidocranial dysplasia
Ref.3
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Cleidocranial dysplasia
Ref.3
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Cleidocranial dysplasia
Ref.3
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Cleidocranial dysplasia
Ref.3
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Cleidocranial dysplasia
Ref.3
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Missing Teeth

• 310, excluding 3rd molars
• Hypodontia
• Oligodontia
• Anodontia
• 8 gt 5 gt 2 gt 1
• 1. Ectodermal
• dysplasia
• 2. orofaciodigital
• syndrome

Ref.1
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Submergence
Infraocclusion, Secondary retention, Reimpaction,
Reinclusion

• most affect 89y/o children and teeth D E
• PDL absent , ankylosis
• Occlusal and periodontal problems

Ref.3
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ectodermal dysplasia
Ref.1
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Ectodermal dysplasia
Ref.3
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SIZE OF TEETH

• True generalized type and relative type
• Macrodontia
• Hemangioma, hemihypertrophy of the face,
  pituitary giantism
• Microdontia
• pituitary dwarfism
• supernumerary teeth, 3rd molars, lateral incisors

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Macrodontia
Microdontia
Ref.1
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ERUPTION OF TEETH

• Transposition
• Two teeth exchanged positions
• 3 4 3 2, 657

Ref.1
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Transposition
Ref.3
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Gemination (twinning)
Altered Morphology of Teeth

• -Division of a single tooth bud
• primary dentition , esp. incisor region
• complete twinning increase tooth number
• pulp chamber is single enlarged, maybe partial
  divided

Ref.3
Ref.1
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Fusion (synodontia)
-Adjacent tooth germs combined with dentin or
enamel

• bifid crown or two recognizable teeth, reduced
  number of teeth
• more common in the primary dentition, esp.
  anterior region

Ref.1,2
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Concresence
- Roots of two or more teeth united by cementum

• Fusion after root formation
• Traumatic injury or crowding
• Pre-extraction x-ray check
• maxillary molars 3rd molar a supernumerary
  tooth

Ref.1
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Taurodontism
-Longitudinal enlarged pulp chamber, increased
distance between CEJ to the bifurcation

• normal crown size tooth length, shortened roots
  
• not recognizable clinically
• most in molars
• Trisomy 21

Ref.1
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Dilaceration

• A sharp bend or curve in the crown or root
• maxillary premolars

Ref.1
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Dens in Dente(dens invaginatus)

• - Infolding of the outer enamel surface into
  the interior
• at the anatomically defined pit
• caries?pulpal disease
• coronal type enamel organ infolding into the
  dental papilla 2gt1gt4,5gt3
• radicular type invagination of Hertwigs
  epithelial root sheath, lined with cementum
• 4, 7

Ref.1
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Dens in Dente
radicular type
coronal type
Ref.1
Dilated odontome
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Dens Evaginatus

• - Outfolding of enamel organ
• a tubercle on occlusal surface,
• with enamel surface dentin core,
• pulp horn often extends into the
• evagination
• premolar or molar
• pulp infection due to fracture

Ref.1 Ref.2
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Amelogenesis Imperfecta

• -Disturbance in enamel development
• Normal dentin root
• autosomal dominant or recessive , X-linked
• 1.Hypoplastic type
• Thin enamel with pitted, rough or smooth glossy
  surface yellowish to brown
• undersized, squared crown, lack of contact
• flat occlusal surface low cusps, attrition
• 2.Hypomaturation
• normal thickness of enamel, but mottled surface
  cloudy white, yellow or brown, opaque in color
• softer than normal
• same density as dentin
• 3.Hypocalcified type
• normal thickness of enamel, density less than
  dentin
• normal size shape when erupt, abrade or
  fracture away rapidly
• permeability increase, darkened stained
• 4.Hypomaturation-hypocalcified with taurodontism
  

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Amelogenesis Imperfecta
Hypocalcified type
Hypoplastic type
Ref.1
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Dentinogenesis Imperfecta (hereditary opalescent
dentin)

• Autosomal dominant hereditary
• Type I DI OI (osteogenesis imperfecta)
  COL1A1, COL1A2
• Type II Isolated DI. (1/8000)
  DSPP
• Type III DI of the Brandywine type
  DSPP
• A racial isolate in Maryland,
  
• DI multiple pulp exposures in deciduous
  teeth
• enamel fractures, attrition severely
• dark brown to black
• Radiographic Features of D.I.
• bulbous crown, normal size, constriction of the
  cervical area
• short slender roots, occlusal attrition
• partial or complete obliteration of the pulp
  chambers, root canals absent or threadlike

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Dentinogenesis Imperfecta
Ref.1
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Dentin Dysplasia

• -autosomal dominant disturbance
• rare (1100,000)
• Type I (radicular)
• normal color shaped in both dentition
• malaligned arch, drifting and exfoliate with
  little or no trauma
• short or abnormal root shaped, pulp chamber
  root canals completely filled in before eruption
• 20 of teeth with type I disease have apical
  radiolucencies

Ref.1
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Dentin Dysplasia

• TypeII (coronal)
• primary dentition appears as D.I., but permanent
  dentition is normal
• obliterated of the pulp chamber reduced root
  canals after eruption
• roots are normal in shape proportion

Ref.1
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Regional Odontodysplasia (odontogenesis
imperfecta)

• - hypoplastic hypocalcified of both dentin
  enamel
• only a few adjacent teeth in a quadrant affected
  either primary or permanent teeth
• central incisors gt lateral incisors gtcanines
  (maxillary)
• delayed eruption
• ghostlike appearance in image
• large pulp chamber wide root canals, roots are
  short poorly outlined
• thin enamel , less dense as usual

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Regional Odontodysplasia
Ref.1
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Enamel Pearl (enameloma, enamel
drop, enamel nodule)

• - small globule of enamel on the roots furcation
  area of molars
• prevalence 3
• mesial or distal aspect in Max. molar and buccal
  or lingual in Mand. molars

Ref.1
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Talon Cusp

• - Anomalous hyperplasia of the cingulum of a
  Max. or Mand. incisor ?a supernumerary cusp
• T shaped in incisal view
• Differential diagnosed with supernumerary tooth

Ref.1 Ref.2
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Turners Hypoplasia (Turners tooth)

• -a type of enamel hypoplasia
• - local hypoplastic or hypomineralized defect
  in crown of a permanent tooth
• extension of a periapical infection or mechanical
  trauma from deciduous predecessor
• most common in lower premolars

Ref.2,3
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Turners tooth(enamel hypoplasia)
Ref.1
Ref.3
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Congenital Syphilis

• 30 pt develop dental hypoplasia
• Hutchinsons incisors mulberry molars
• not all pt with Hutchinsons teeth or mulberry
  molars will have congenital syphilis

Hutchinsons incisors (screw driver shape)
Ref.1
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Acquired Pathologic Conditions

• Attrition
• -Physiologic wearing from occlusal contacts
• Incisal, occlusal and interproximal
  surfaces(contact points)
• Depends on the abrasiveness of diet, salivary
  factors, mineralization, emotional tension
• Bruxism--pathologic condition
• Crown shorten, reduction of pulp chamber canals

• Abrasion
• -Nonphysiologic wearing by contact with foreign
  substances
• Factitious habits or occupational hazards
• tooth brushing, flossing, pipe smoking, opening
  hairpins with teeth

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Tooth Brushing Injury

• V-shaped groove in cervical area
• Sensitive
• Maxillary premolars gtcanines gt incisors
• R-L defect at cervical level, well-defined
  semilunar shapes

Ref.1 Ref.3
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Dental Floss Injury

• Cervical portion of proximal surfaces just above
  gingiva
• Narrow semilunar R-L, distal surface often deeper
  than mesial

Ref.1
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Erosion

• -Chemical action not involving bacteria
• Contact acid with teeth
• 1. chronic vomiting or acid reflux from
• GI disorders
• 2. consumes large amounts of acid
• foods
• 3. occupational exposure
• Regurgitated acids attack lingual surfaces
  diet--labial industrialall surfaces
• Radiolucent defect on the crown

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Resorption

• -Removal of tooth structure by odontoclast
• Chronic infection (inflammation), excessive
  pressure and function, tumors and cysts

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Internal Resorption

• - within the pulp chamber or canal, involves
  resorption of surrounding dentin, results in
  enlarged pulp space

Ref.1
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Internal Resorption
Ref.1
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External Resorption

• -outer surface of tooth resorbed, most commonly
  in root surface
• Localized inflammatory lesions, reimplanted
  teeth, tumor cyst, excessive mechanical(orthodon
  tic) and occlusal forces, impactions
• Common sites apical cervical (lateral root
  surface)

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Apical ER
Lateral root surface ER
Ref.1
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Secondary Dentin

• - Dentin deposited in pulp chamber after primary
  dentin formatted completely
• Normal aging process
• tertiary dentin pathologic condition after
  chronic trauma
• Reduction in size of pulp chamber and canals
• Begins in the region adjacent to source of
  stimuli and alters normal shape of chamber

Ref.1
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Pulp Stone

• -- Foci of calcification in the pulp
• R-O within pulp chambers or root canals or
  extending from pulp chamber into root canals,
  most common in molars
• No uniform shape or number

Ref.1
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Pulpal Sclerosis

• - Diffuse calcification in pulp chamber and
  canals
• Correlation strongly with age
• Generalized, ill defined collection of fine RO
  throughout pulp chamber and canals

Ref.1
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Hypercementosis

• -Excessive deposition of cementum on roots
• 1.supraerupated tooth after opposing
• tooth loss
• 2.periapical inflammatory lesions
• 3.hyperocclusion or fractured
• 4.Pagets disease
• 5.hyperpituitarism
• Smooth or irregular enlargement of root with
  lamina dura and PDL space

Ref.1
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Summary

• DEVELOPMENTAL ABNORMALITIES
• NUMBER OF TEETH
• SIZE OF TEETH
• ERUPTION OF TEETH
• ALTERED MORPHOLOGY OF TEETH
• Fusion(synodontia)
• Concresence
• Gemination(twinning)
• Taurodontism
• Dilaceration
• Dens in dente (dens invaginatus)
• Dens evaginatus
• Amelogenesis imperfecta
• Dentinogenesis imperfecta
• Dentin dysplasia
• Enamel pearl
• Talon cusp
• Turners hypoplasia (Turners tooth)

• ACQUIRED PATHOLOGIC CONDITIONS
• Attrition
• Abrasion
• Tooth brushong injury
• Dental floss injury
• Erosion
• Resorption
• Internal resorption
• External resorption
• Secondary dentin
• Pulp stone
• Pulpal sclerosis
• Hypercementosis