Dental Anomalies II Flashcards
what is gemination
attempt of a single tooth bud to divide, resulting in a bifid crown
- affects deciduous and permanent dentition
what are the clinical and radiographic features of gemination
- tooth count is normal when anomalous tooth is counted as one
- MC in anterior maxilla
- RG: bifid crown with shared root canal
what is fusion
- union of two normally separate tooth buds -> form a joined tooth
- affects deciduous and perm dentition
what are the clinical and radiographic features of fusion
- tooth count reveals missing tooth when anomalous tooth is counted as one
- MC in anterior mandible
- RG: separate canals usually present
what is concrescence
two fully formed teeth joined by root surfaces by cementum
what are the clinical features of concrescence
- most common in posterior maxilla
- often involved 2nd molar- root in close proximity to 3rd molar
- may result from postinflammatory/carious tooth
what are the clinical features of a talon cusp
- well delineated additional cusp located on the surface of an anterior tooth
- extends at least half the distance between CEJ and incisal edge
- MC in perm dentition
- MC in maxillary lateral > central incisor
- MC in asian, inuit, native american
what are the clinical features of dens evaginatus
- cusp-like elevation of enamel
- central groove or lingual ridge of the buccal cusp
- observed in posterior teeth ( premolar MC)
- MC in mandible
- MC in asian, inuit, native americans
- may result in occlusal interferences
- frequent associated with shovel shaped incisors
what are the clinical features of dens invaginatus
- deep surface invagination of the crown or tooth lined by enamel
- MC permanent maxillary lateral and central incisors
- tooth within a tooth
- opening may become carious
what are the clinical features of an enamel pearl
-presence of enamel in an unusual location
- MC max molars > mand molars
- MC at furcation area or near CEJ
- precludes normal periodontal attachment
describe taurodontism
- enlargement of the body and pulp chamber of a multi rooted tooth
- isolated or syndromic
- may be associated with cleft lip/palate
what are the clinical features of taurodontism
- pulp chambers- increased apico- occlusal height
- mild to severe cases
- most common in permanent teeth
- may appear bilateral
what is hypercementosis
- non neoplastic deposiiton of excessive cementum along the root
- isolated or involve multiple teeth
- associated with local factors like trauma, inflammation
if there is a generalized pattern of hypercementosis consider:
paget disease
what are the clinical and radiographic features of hypercementosis
- thickening or blunting of the root surface
- MC in mandibular molars
- frequency increases with age
what is dilaceration
- abnormal angulation or bend in the root
- majority arise following injury that displaces the calcified portion of the tooth germ
- idiopathic or syndromic
what are the clinical features of dilaceration
- MC mand 3rd molard > max 2nd premolar > mand 2nd molar
- bend occurs anywhere along the root
- complications in extractions or endo
what are the developmental alterations affecting structure
- amelogenesis imperfecta
- dentinogenesis imperfecta
- dentin dysplasia
- regional odontodysplasia
what is amelogenesis imperfecta
- a large group of hereditary conditions that show alterations in the enamel in the absence of systemic disase
amelogenesis imperfecta involved alterations in the enamel that may arise at any of the following stages:
- matrix formation: hypoplastic
- mineralization of matrix: hypocalcified
- maturation of the enamel: hypomaturation
what is the inheritance of amelogenesis imperfecta and which denintitions are affected
- AD, AR, X linked inheritance
- affects deciduous and permanent
what are the clinical features of amelogenesis imperfecta
- hypoplastic type: may see pits, rows of missing enamel
- hypocalcified type: enamel is soft, “cheesy”, easily lost. yellow, brown or organge
- hypomaturation type: enamel is soft: opaque, white, brown
what is dentinogenesis imperfecta
- hereditary disturbance in the formation of dentin in the adsence of any systemic disorder
- DSPP gene mutation
- AD inheritance
- affects deciduous and permanent dentition
what are the clinical features of dentinogenesis imperfecta
- deciduous teeth affected more severely
- permanent teeth: most common in incisors and 1st molars
- MC in white patients
- blue to brown discoloration, distinct translucence
- enamel strips from poorly formed dentin
what are the radiographic features of dentinogenesis imperfecta
- bulbous crown, cervical constriction, thin roots
- early obliteration of root canal and pulp chamber
- OR
- normal to enlarged pulp chambers
-significantly enlarged pulp are called shell teeth
what is dentin dysplasia I
- loss of organization of root dentin leads to shortened root length
- AD inheritance
- type II thought to be a variant of dentiogenesis imperfecta
- deciduous and permanent teeth affected
what are the clinical features of dentin dysplasia I
- enamel and coronal dentin well formed
- radicular dentin loses organization -> short roots
- tooth mobility and premature exfoliation
what are the radiographic features of dentin dysplasia I
- deciduous teeth: little or no detectable pulp, very short roots
- permanent teeth: crescent shaped pulpal remnant, short roots
what is regional osdontodysplasia
- nonhereditary developmental abnormality of teeth that affects enamel, dentin and pulp
- most cases are idiopathic, some syndromic
- may be due to alteration of vascular supply
what are the clinical findings in regional odontodysplasia
- enamel, dentin and pulp affectde
- MC in maxillary anterior teeth
- dx at time of eruption of primary and permanent
- affects several teet, quadrant distribution
- impacted teeth, delayed eruption
- erupted teeth are malformed, caries rampant
- hyperplasia of overlying soft tissue
what are the radiographic findings of regional odontodysplasia
- extremely thin enamel and dentin
- enlarged pulp chambers- ghost teeth
- short roots may be observed
what is segmental odontomaxillary dysplasia
- developmental disorder, affects jaw and overlying soft tissue
what are the clinical features of segmental odontomaxillary dysplasia
- painless, unilateral enlargement of maxillary bone
- usually dx during childhood
- hyperplasia of overlying gingiva
- primary teeth may be hypoplastic
- maxillary premolar teeth may be missing
what are the radiographic features of segmental odontomaxillary dysplasia
- thickened trabeculae, often vertically oriented
- radiopaque, granular appearance
- maxillary sinus may be smaller
what is the tx for segmental odontomaxillary dysplasia
- remains relatively stable, may not require tx
- surgical recontouring
