Chapter 2: Abnormalities of Teeth Flashcards
___ in the developing tooth germ are extremely sensitive to external stimuli
ameloblasts
what are some examples of environmental factors that can result in tooth abnormalities?
- birth-related trauma
- chemicals (tetracycline and fluoride)
- radiation therapy
- infections (chicken pox, syphilis)
- malnutrition (vitamin deficiency)
- metabolic disorders
- neurologic disorders
when do crowns of deciduous teeth develop?
14 weeks gestation through 12 months of age
when do crowns of permanent teeth develop?
from 6 months of age to 15 years
___ is characterized as enamel defects seen in permanent teeth casued by periapical inflammatory disease of the overlying deciduous tooth
turner’s hypoplasia
aka turner’s tooth
where is turner’s hypoplasia most commonly seen?
in the permanent bicuspids because of their relationship to the overlying deciduous molars
___ is excess amounts of fluoride that can result in significant enamel defects
dental fluorosis
what is the major concern of dental fluorosis?
aesthetics (anterior teeth)
the critical period for clinically significant dental fluorosis is during ___, when anterior teeth are developing
the second and third years of life
optimum fluoridation of drinking water is around ___ppm
0.7ppm
to avoid dental fluorosis, ___ should be avoided in children less than 2 years
fluoridated toothpaste
what are the tooth abnormalities caused by congenital syphilis?
- rare
- anterior teeth are termed “hutchinson’s incisors”
- look like a flathead screwdriver
- altered posterior teeth called “mulberry molars”
- hutchison’s triad
___ is the loss of tooth structure caused by tooth-tooth contact
attrition
___ is the pathologic wearing away of tooth structure
abrasion
what is hutchison’s triad?
- hutchison’s teeth
- interstitial keratitis (corneal scarring)
- 8th nerve deafness
- *other manifestation is a saddle nose (not part of the triad)
what is demastication?
exhibits features of both attrition and abrasion (ex. chewing tobacco between opposing teeth)
___ is the loss of tooth structure caused by a nonbacterial chemical process
erosion
erosion from dental exposure to gastric secretions is termed ___
perimolysis
(can be from GERD or bulemia)
___ is the loss of tooth structure from occlusal stresses that create repeated tooth flexure
abfraction
what are 5 general things that can be caused by developmental disturbances of teeth?
- size (macrodontia, microdontia)
- eruption (impaction, ankylosis)
- shape (gemination, fusion, concrescence, dilaceration)
- structure (accessory cusps, dens evaginatus, dens invaginatus, taurodontism)
- number (anodontia, hypo-, hyper-)
___ is lack of tooth development
anodontia
anodontia is rare, and most cases occur in the presence of ___
hereditary hypohidrotic ectodermal dysplasia
___ is the lack of one or more teeth
hypodontia
___ is the lack of 6 or more teeth
oligodontia
the absence of a deciduous tooth is likely to also miss the ___
associated permanent tooth
which teeth are most commonly affected by hypodontia?
3rd molars first, thend 2nd premolars and lateral incisors
___ is a term for a supernumerary tooth/teeth
hyperdontia
the most common site of hyperdontia is ___
the maxillary incisor region (mesiodens)
___ is abnormal eruption where the tooth erupts in an abnormal location
transposition
___ is the failure of a tooth to fully erupt
ankylosis
___ is a single englarged tooth or joined tooth in which the tooth count is normal when the anomalous tooth is counted as one
gemination
___ is characterized by many supernumerary teeth and the failure of clavicles to form, so the shoulders will be in a forward and medial position
cleidocranial dysplasia
___ is described as a single enlarged tooth or joined tooth in which the tooth count reveals a missing tooth when the anomalous tooth is counted as one
fusion
___ is characterized by a traumatic ulcer of the soft tissues due to natal teeth
riga-fede disease
___ is a bend in the tooth root
dilaceration
___ is usually seen in association with shovel-shaped incisors
dens invaginatus
what are the most commonly impacted teeth?
mandibular 3rd molars > maxillary 3rd molars > maxillary canines
what is the common clinical presentation dens evaginatus?
- typically occurs on premolar teeth
- usually bilateral and more common in the mandibular arch
dens evaginatus has what prevalence in native americans and the inuit populations? (also common in asians)
100%
densi-in-dente is also known as ___
dens invaginatus
what is dens-in-dente
- tooth within a tooth
- deep surface invagination of the crown or root that is lined by enamel
what is the frequency of dens-in-dente?
permanent lateral incisors > central incisors > premolars > canines > molars
___ is an enlargement of the body and pulp chamber of a multi-rooted tooth, with apical displacement of the pulpal floor
taurodontism
taurodontism can be isolated or syndromic. what are 3 examples?
- kleinfelters syndrome (XXY)
- amelogenesis imperfecta
- tricho-dento-osseous syndrome
what is tricho-dento-osseous syndrome?
in addition to the dental fillings, the predominant systemic changes are present variably and include kinky hair, osteosclerosis (base of skull and mastoid process), and brittle nails
___ is non neoplastic deposition of excessive cementum that is continuous with the normal radicular cementum
hypercementosis
what are the local factors of hypercementosis?
- occlusal trauma
- adjacent inflammation (pulpal, periapical, periodontal)
what are the systemic factors of hypercementosis?
Paget’s disease of bone is strongly associated with generalized hypercementosis
what is the frequency of dilaceration?
mandibular 3rd molars > maxillary 2nd molars > mandibular 2nd molars
___ is described as developmental alterations in the structure of enamel in the absence of a systemic disorder
amelogenesis imperfecta
amelogenesis imperfecta is divided into what 3 defects?
- elaboration (aka deposition) of the enamel matrix (hypoplastic)
- mineralization of the matrix (hypocalcified)
- maturation of the enamel (hypomaturation)
does amelogenesis imperfecta involve both the deciduous and permanent dentition?
yes
enamel pearls are the most common form of ___ and are found most frequently on the roots of maxillary molars
ectopic enamel
hypoplastic amelogenesis imperfecta involves inadequate deposition of ___
enamel matrix
what type of amelogenesis imperfecta involves any matrix present that is mineralized appropriately and radiographically contrasts well with underlying dentin?
hypoplastic amelogenesis imperfecta
describe the different subtypes of hypoplastic amelogenesis imperfecta and their clinical manifestations
- pinpoint pits scattered across tooth surface
- thin, hard, smooth, glossy enamel; teeth shaped like crown preps; color is opaque white to transclucent brown
- thin, hard, rough enamel; yellow teeth
- total lack of enamel formation; yellow-brown dentin
hypomaturation amelogenesis imperfecta invovles a defect in the ___
maturation of the enamel’s crystal structure
what type of amelogenesis imperfecta involves enamel matrix that is laid down appropriately and begins to mineralize?
hypomaturation amelogenesis imperfecta
describe the clinical presentation of hypomaturation amelogenesis imperfecta
- teeth are normal in shape
- mottled, opaque white-brown-yellow discoloration
- enamel is soft and chips away from dentin
what are the 3 different patterns of hypomaturation amelogenesis imperfecta?
- pigmented: surface enamel is agar-brown
- x-linked: varies
- snow-capped: white opaque enamel on the incisal/occlusal 1/3
what type of amelogenesis imperfecta involves matrix that is laid down appropriately and does NOT mineralize?
hypocalcified
describe the clinical presentation of hypocalcified amelogenesis imperfecta
- teeth are appropriately shaped
- enamel is soft and easily lost
- enamel starts as yellow-brown or orange and becomes brown to black with rapid calculus apposition
what are the main problems with amelogenesis imperfecta?
- esthetics, dental sensitivity, loss of vertical dimension
- increased prevalence of caries, anterior open bite, delayed eruption, tooth impaction, gingival inflammation
___ is a hereditary developmental disturbance of dentin in the absence of any systemic disorder
dentinogenesis imperfecta
dentinogenesis imperfecta involves a mutation of the ___ gene
dentin sialophosphoprotein (DSPP)
if dentinogenesis imperfecta occurs with osteogenesis imperfecta, it is termed ___
- osteogenesis imperfecta with opalescent teeth
- blue sclera
- mutation of the COL1A1 or COL1A2
dentinogenesis imperfecta occurs most commonly in what population?
caucasians
are both dentitions affected by dentinogenesis imperfecta?
yes, and deciduous teeth are affected most severely
with dentinogenesis imperfecta, are full dentures commonly needed?
yes, usually by age 30
how does dentinogenesis imperfecta present clinically?
- blue-to-brown discoloration with distinctive translucence
- shell teeth = normal thickness enamel with extremely thin dentin and dramatically enlarged pulps
how does dentinogenesis imperfecta present radiographically?
- bulbous crowns
- cervical constriction
- thin roots
- early obliteration of root canals and pulp chambers
describe type I dentin dysplasia
- “rootless teeth”
- autosomal dominant
- enamel and coronal dentin are normal
- radicular dentin loses organization and is shortened dramatically
- “stream flowing around boulders”
describe type II dentin dysplasia
- autosomal dominant
- root length is normal
- blue-to-amber-to-brown translucence
- radiographically - bulbous crowns, cervical constriction, thin roots, early obliteration of the pulp
- altered pulpal anatomy - thistle tube-shaped, pulp stones
dentin dysplasia does not have a correlation with ___ or ___
systemic disease or dentinogenesis imperfecta
which type of dentin dysplasia is closely related to dentinogenesis imperfecta?
type II
___ is a localized, non-hereditary developmental abnormality of teeth with extensive adverse effects on the formation of enamel, dentin, and pulp
regional odontodysplasia
they look like “ghost teeth”
