02.06 abnormalities of shape, color, development Flashcards
abortive attempt by a single tooth bud to divide
gemination
-there would be 21 teeth instead of 20
the union of normally discrete teeth
two separate root canals
fusion
the fusion of two teeth along the root surface
two separate root canals
concrescence (it occurs post erruptive)
complete cleavage of a tooth bud resulting in the formation of a supernumerary tooth
-the completion of _______
Twinning, which is the completion of gemination
-the teeth will be mirror images
“bull-like teeth”
body of the tooth enlarged, roots reduced in size
-increased risk of pulp exposure during cavity preparation
-very large pulps
Taurodontism
-both primary and permanent teeth involved
the tooth fold in on itself, usually on lingual of maxillary laterals
Dens-in-dente or Dens Invaginatus
what are the most frequently missing teeth
mandibular 2nd bicuspid (33%), then max lateral incisor (27%), then max 2nd pm, then mand lateral incisors
-3rd molars 25%
- (polydactyly) patient with 6 fingers on each hand
- autosomal recessive
- short stature
- cardiac abnormalities
Ellis Van Creveld Syndrome or Chondroectodermal dysplasia
- AD inheritance
- missing maxillary incisors
- Degeneration of the anterior chamber of the eye
Rieger syndrom
syndromes associated with missing teeth
…..
- Ellis Van Creveld Syndrome (Chondroectodermal Dysplasia)
- Rieger syndrome
- oro-facial-digital syndrom
- hypohidrotic ectodermal dysplasia……
- lack of teeth is often presenting complaint at 12-18 months of age
- defects in the enamel may resemble amelogenesis imperfecta
- dental abnormalities may be the only striking feature
ectodermal dysplasia
- lack of teeth is often presenting complaint at 12-18 month
- defects in enamel may resemble AI
- Dental abnormalities may be the only striking feature
ectodermal dysplasia
-they will also have lack of alveolar development
permanent teeth present in ectodermal dysplasia
- commonly 4-14 teeth present
- more teeth in the maxilla
- most commonly missing are mand incisors and pms, followed by max pms
- most commonly present: max CI, k, max and mand first molars
- conical and peg shaped teeth
Hyperdontia
- extra teeth
- males affected 2:1 over females
- maxillary anterior (mesiodens) most common (9X more common)
- AD most common with lack of penetrances
- AD,
- multiple osteomas
- intestinal polyps with high malignancy rate
Gardners syndrome
Syndromes with extra teeth
- Gardners Syndrome
- Cleidocranial Dysplasia
- cleft lip and plalate
what are the three types of amelogenesis imperfecta?
1-hypoplastic
2-hypocalcified
3-hypomature
type of AI, hard, thin enamel, small teeth, occaisionally tapered
Hypoplastic AI
type of AI
- normal thickness, soft and abrades easily
- pitted surface
- varieable radiodensity-moth eaten appearance
hypocalcified
type of AI
- soft enamel of normal thickness
- fractures and flakes away
- radiographically can not distinguish enamel from dentin
hypomature
Types of DI
types I, II, III
type of DI
- hereditary opalescent dentin-NEVER occurs with OI
- both dentitions equally affected
- one of the most common inherited defects in man
- sporadic cases very rare
- almost complete penetrance
type II
type of DI
- always occurs with osteogenesis Imperfecta (OI), but not visa versa
- primary dentition more severely affected than permanent
- great variability within a family
type I
worst and most rare type of DI
-shell tooth appearance on radiographs
type III, bradywine type
large pulp chambers with pulpal extensions to the enamel
vitamin D- resistant rickets
- “ghost teeth”
- localized arrest of tooth development
- teeth do not develop, only outline of crown is evident
regional odontodysplasia
