number
- hypodontia
2. hyperdontia
size
- microdontia
2. macrodontia
structure
- amelogenesis imperfecta
- dentinogenesis imperfecta
- dentin dysplasia
shape
- gemination
- fusion
- accessory cusps
- dens invaginatus
- dens evaginatus
- ectopic enamel
- taurdontism
- hypercementosis
- accesory roots
- dilaceration
hyperdontia (supernumerary teeth) is an anomaly of what?
of initiation and proliferation
prevalence of hyperdontia is higher in which race?
Asians and African Americans
hyperdontia occurs more in the maxilla or mand?
maxilla
T/F: location of hyperdontia can vary
true…
mesiodens
paramolar
T/F: shape of supernumerary tooth is often abnormal
true
mesiodens
extra tooth right between max central incisors
when do neonatal teeth erupt?
within 30 days of birth
most natal/neonatal teeth are what?
primary tooth (not supernumerary)
majority of natal/neonatal teeth are which tooth?
mand incisor
features of natal/neonatal teeth
- thin
- mobile
- rootless
problems with natal/neonatal teeth
- can be aspiration risk
2. cause feeding problems
tx of natal/neonatal teeth
extraction
hypodontia
lack of tooth development
cause of hypodontia
familial tendency and genetic component
hypodontia is missing how many teeth?
≤ 1-5 teeth
oligodontia
missing 6 or more teeth
T/F: hypodontia is more prevalent in perm dentition
true
congenitally missing teeth in perm denition
3rd molars > mand 2nd PM > max lateral incisor > max 2nd PM
congenitally missing teeth in primary dentition
max lateral incisor
microdontia and macrodontia are anomalies of what?
proliferation and morphodifferentiation
true generalized microdontia and macrodontia
small/large teeth in normal sized jaw
relative generalized microdontia and macrodontia
normal or small teeth in large jaw or normal or large teeth in small jaw
T/F: single tooth macrodontia is common
false, rare
T/F: single tooth microdontia is rare
false, common
what is the most common microdontia tooth?
lateral incisor (peg lateral)
what is the second most common microdontia tooth?
3rd molar
T/F: isolated macrodontia is often bilateral
true
what should be ruled out if dx is isolated macrodontia?
gemination/fusion
primary tooth most affected by macrodontia?
2nd molar, which could interfere with eruption
conjoined teeth is an anomaly of what?
proliferation and morphodifferentiation
germination
- single enlarged tooth with normal tooth count
2. division of single tooth
fusion
- single enlarged tooth with fewer than normal tooth count
2. conjoining or two separate primary teeth
T/F: conjoined teeth occur more often in permanent dentition
false, primary
concrescence teeth are joined where?
cementum
where does germination usually occur?
anterior (incisors and canines)
complications with germinated tooth
- can have difficulty erupting
- can block out other teeth
- caries can develop in area of cleft
where does fusion usually occur?
anterior
what causes fusion?
can be familial
complications with fusion tooth
- congenital absence of successor tooth
2. caries may develop in area of fusion
dens invaginatus (dens in dente)
tooth in a tooth
dens invaginatus is what type of anomaly?
developmental
what causes dens invaginatus (dens in dente)?
lingual invagination of inner enamel epithelium
which tooth does dens invaginatus (dens in dente) usually affect?
max lateral incisor
T/F: dens invaginatus (dens in dente) is common in primary dentition
false, uncommon
features of dens invaginatus (dens in dente)
- tooth has deep lingual pit
2. prominent cingulum
radiographs of a dens invaginatus (dens in dente) tooth shows what?
oval invagination to crown or root
complications with dens invaginatus (dens in dente)
- often becomes carious
2. pulp may become necrotic easily
tx for dens invaginatus (dens in dente)
tx’d w/ sealant, composite, or possible endo
dens evaginatus
cusp-like enamel in central groove/lingual ridge of PM or molar
which tooth is most often involved with dens evaginatus?
bilateral mand PMs
T/F: dens evaginatus is common in primary teeth
false, rare
what can dens evaginatus be associated with?
shovel-shaped incisors
tx for dens evaginatus
(progressive) enameloplasty
complications with dens evaginatus
- may contain pulp
- can cause traumatic occlusion
- can fracture off
- can cause deviation of tooth eruption
- may require endo
talon cusp
cusp on lingual of anterior teeth
complication with talon cusp
may contain pulpal tissue
tx of talon cusp
- progressuve enameloplasty
- sealant
- composite
- potential endo
root dilaceration
abnormal angulation or curvature of root
cause of root dilaceration
- idiopathic
2. may be due to intrusion or trauma of primary tooth affecting developing tooth
complications of root dilaceration
- can delay/inhibit eruption –> may require ortho
2. can create difficult ext
developmental alterations to tooth structure
- molar-incisor hypomineralization (MIH)
- amelogenesis imperfecta
- dentinogenesis imperfecta
- dentin dysplasia
- enamel hypoplasia
- fluorosis
- regional odontodysplasia
molar-incisor hypomineralization (MIH) affects which tooth?
perm 1st molars and incisors
cause of molar-incisor hypomineralization (MIH)
due to ameloblast fxn problem
origin of molar-incisor hypomineralization (MIH)
unknown but likely multifactorial
- abx
- nutritional deficiency
- pre-term birth
- toxins
appearance of molar-incisor hypomineralization (MIH) teeth
teeth are “chalky” and mottled
complications of molar-incisor hypomineralization (MIH)
- teeth are more susceptible to caries
2. teeth are often sensitive
tx for molar-incisor hypomineralization (MIH) depends on what?
severity/presentation
tx for molar-incisor hypomineralization (MIH)
- remineralization
- restoration
- crown
- extraction
amelogenesis imperfecta (AI)
group of conditions caused by gene mutation
what is disrupted/disturbed in amelogenesis imperfecta (AI)?
enamel fxn
4 major types of amelogenesis imperfecta (AI)
- hypoplastic
- hypomaturation
- hypocalcified
- hypoplastic-hypomaturation
inherited gene mutation for amelogenesis imperfecta (AI)
can be…
- autosomal dominant
- autosomal recessive
- x-linked
T/F: amelogenesis imperfecta (AI) affects only the permanent dentition
false, affects primary and perm
hypoplastic amelogenesis imperfecta (AI)
inadequate enamel matrix deposition (thin enamel)
inheritance of hypoplastic amelogenesis imperfecta (AI)
autosomal dominant
T/F: some pts with hypoplastic AI have anterior open bite
true
appearance of hypoplastic AI
enamel appearance varies…
- pitted
- rough
- smooth
- yellow
- brown
dentinogenesis imperfecta (DI)
defect of predentin matrix
dentin of pts with dentinogenesis imperfecta (DI)
hereditary opalescent dentin
cause of dentinogenesis imperfecta (DI)
mutation of DSPP (dentin sialophosphoprotein) gene
T/F: dentinogenesis imperfecta (DI) affects only the perm dentition
false, both primary and perm
type 1 dentinogenesis imperfecta (DI)
osteogenesis imperfecta + DI
type 2 dentinogenesis imperfecta (DI)
isolated DI
type 3 dentinogenesis imperfecta (DI)
Brandywine DI
inheritance for dentin dysplasia type I
autosomal dominant inheritance
what does the primary teeth look like in pts with dentin dysplasia type I?
look like DI
what does the perm teeth look like in pts with dentin dysplasia type I?
appear normal…
- normal shape and color
- roots/pulp are thistle-tubed
T/F: pulp stones are common for pts with dentin dysplasia type I
true
dentin dysplasia type 2
defect in root sheath
inheritance of dentin dysplasia type 2
autosomal dominant
features of pts with dentin dysplasia type 2
- teeth appear normal clinically
- teeth have short or obliterated roots
- pulp is obliterated or crescent-shaped
fluorosis
due to excess intake of fluoride during tooth development
T/F: municipal water have higher fluoride levels than wells/pumps
false, less
features of fluorosis
- chalky/streaky white enamel
- brown stains
- pits
mild fluorosis may cause teeth to what?
be less prone to caries
moderate/severe fluorosis causes what?
pitting and makes teeth more prone to caries
tx for mild/moderate fluorosis
- bleaching
2. microabrasion
tx for moderate/severe fluorosis
- crowns
- veneers
- composite restorations
what might fluorosis appear like?
amelogenesis imperfecta
regional odontodysplasia is also called what?
odontogenesis imperfecta “ghost teeth”
T/F: regional odontodysplasia is common
false, rare, non-hereditary
which part of the tooth is affected by regional odontodysplasia?
- enamel
- dentin
- pulp
radiographic appearance of regional odontodysplasia
dark, undefined
complications with regional odontodysplasia
- teeth may not erupt properly
2. easily infected
T/F: regional odontodysplasia is only isolated to a region (quad)
false, can be global too