Radio anomolies Flashcards
dental anomolies may be what in nature?
developmental or acquired
Hyperodontia
Teeth in excess of the normal complement (more than what there should be like having 4 of a molar)
Maxillary incisors hyperdontia name
mesiodens
Maxillary fourth molars and Mandibular fourth molars names
- distodens,
- paramolars
tooth type for hyperdontia prevalence in order:
max I>max M> man M> PM> C/LI
what can be seen here?
mesiodens
cystic change of supernumerary teeth
cystic change of follicle may or may not occur
increased likelyhood with exposure to inflammatory mediators
probability inversely related to age, however surgery better tolerated by younger pts
what can be seen here? where is it located?
odontoma, moves D with a D shift so this is located on palatal aspect (SLOB)
how could CBCT be useful for supernumerary teeth? con?
when there are many, the more there are the harder it becomes to locate them with simple technique (SLOB)
comes at an additonal cost
is there an anomoly? complications?
yes, a supernumary tooth is present at apex of PT tooth= inflammatory mediator present which can cause cystic change but this has yet to occur
the longer this is left the more likely ankylosis becomes too resulting in a difficult removal if problems arise
anomoly?
yes supernumerary tooth
anomoly, complcation?
distodens (3)
potential for pericoronal infection at the mandibular ones
impacted molar removal
best to remove these asap, more likely to undergo cystic degeneration
anomoly
impacted molar but not supernumerary
where is it most likely to have multiple hyperdontia (>1 extra tooth)
PM area
Syndromes with multiple teeth
- Cleidocranial Dysplasia
- Gardner
Cleidocranial Dysplasia additional signs
- Frontal & parietal bossing
- Clavicular aplasia
Gardner Syndrome additional signs
- Autosomal dominant- family Hx
- Multiple osteomas including the jaws
- Colorectal polyps with malignant potential
- Multiple supernumerary teeth
- Lesions of skin (cutaneous epidermoid cysts
and fibromas)
what discussed syndrome is lilkely present
gardner
Problems with Supernumeraries
- Affect eruption of normal complement of
teeth - Cystic degeneration of follicular epithelium of impacted teeth
what issue are supernumerary teeth causing in this child (4.5y)
difficulty with proper eruption
what issue have supernumerary teeth caused in the mandible?
cystic degeneration
Hypodontia
less than the normal tooth complement of an existing dentition; permanent or deciduous
less than one or more of an existing dentition; permanent or deciduous
Anodontia
congenital absence of all teeth
Anodontia v. Oligodontia v. Hypodontia
- Anodontia – agenesis of all teeth
- Oligodontia – congenital lack of > 6 permanent teeth, excluding third molars
- Hypodontia – less than one or more of an existing dentition; permanent or deciduous
types of hypodontia
- Acquired
- Syndromal
- Reduction phenomenon
- Third Molar Agenesis
- Maxillary Lateral Incisors
- Microdontia
- Isolated Agenesis
most common type of hypodontia
acquired
how many syndromes have hypodontia associations
about 150
more common syndromes associated with hypodontia
- ectodermal dysplasia
- oligodontia-colorectal cancer syndrome
- ectodermal dysplasia with oligodontia-colorectal cancer syndrome
- otodental dysplasia – associated with deafness
- Rieger Syndrome – associated with deafness
dental complications of ectodermal dysplasia
hypo or anodontia
malformed teeth
prone to caries (enamel defects and xerostomia)
malformed teeth
can be cone or peg-shaped
malformed teeth: cone/peg shaped
Reduction Phenomenon
- Hypodontia not associated with other multiple system congenital syndrome
- Seen with third molars and maxillary lateral incisors
- Evolutionary trend ?
most common form of the reduction phenom
thrid molar agenesis, 10-25%/ up to 30% have 1-4 missing
comparing top to bottom
bottom image displays man 1 molar missing: could be hypodontia, agenesis, etc.
many other teeth are missing but would need med/tx history to know why
why are the man molars missing here?
likely extracted, note the furcal aleolar bone is still present
Agenesis of Maxillary Lateral Incisor
AMLI
- Uni/bilateral reduction, i.e., peg lateral maxillary incisors
AD inheritence, variable expression possible: - Uni/bilateral agenesis
- a variable manifestation hypodontia
what is missing
Agenesis of Maxillary Lateral Incisor
AMLI
anomoly present?
AMLI, peg/cone shape
AMLI
microdontia
teeth smaller than usual, can affect one (microdont) to many teeth
how would you classify the man 3rd molars
microdonts
microdont
what complication arises with microdonts
diastemas form=food trap and caries
microdont
how common is isolated agenesis (non-third molar)
non-thrid molar hypodontia: 5-10% typical
what issue arises with isolated agenesis
primary teeth may be retained, can be maintained and not require removal in some cases
may also lead to compromised arch form and/or occ discrepancies
isolated agenesis, 1 molar retained
isolated agenesis, 1 canine retained
macrodont
enlarged tooth
marcodont issues
may not fit arch space
sus to caires and perio dx with increased grooves
macrodont
Bulky Incisor or Double tooth
phenomenon
etiologies
form of macrodontia, hard to prove absolute etiology
macrodont likely fusion
macrodont
what could this be classified as?
Fusion, Twinning or
Supernumerary
macrodont
macrodont
dilacerations
- Abnormal angulation or bend in the root (and occasionally the crown) of a tooth
- Some related to trauma during odontogenesis
- idiopathic
dilaceration
Supernumerary Roots
- Extra roots above the complement of roots classically
described for the dentition
1st molar anomoly
3rd root
Supernumerary Roots
* Significant for what considerations?
* Appear to be excellent for>?
- Significant for endodontic or exodontic considerations
- Appear to be excellent prosthodontic abutments
3rd root 1st molar
Li Root of Mandibular First
Molars
- 20% incidence in Asians in a Chinese population (Hong Kong and Taiwan)
- 10-12% in native North American populations
supernumerary roots
Non–carious Loss of Tooth Structure forms
Abrasion – mechanical wear of teeth
Attrition – physiologic wear of teeth
Erosion – chemical wear of teeth
attrition
cervical abrasion
what is seen in both of these?
cervical abrasion
erosion
likely lingual erosion= bulemia
taurodont
enlarged pulp chambers/ smaller roots
what anomoly can be noticed
taurodonts
taurodont etiology
- Idiopathic developmental disorder of odonogenesis causing elongation of the pulp chamber (aka apical
displacement of the pulpal floor) and shorter root appendages - failure of Hertwig’s epithelial sheath diaphragm to invaginate at the proper horizontal level, resulting in a tooth with short root, enlarged body, an enlarged pulp and normal dentin
taurodont
taurodont
when are taurodonts complicated?
endo/extractions
Dens Invaginatus Dens in Dente
incidence rate?
mostly seen where?
- 0.04 – 10% incidence
- Primarily seen in lateral incisors but also centrals, premoalrs, centrals, canines…..
dens in dente
Dens Invaginatus
Dens in Dente types
- Type I – coronal
- Type II – extends apical to CEJ
- Type III – extends through root perforating to apex
dens in dente complication
can act as a food trap= caries
two dens in dente type I
dens in dente type 2
type 3 dens in dente
Dens Invaginatus
Dens in DenteTreatment
restore the coronal pit
talon cusps
drift vs migration
drift: movement of erupted teeth
migration: movement of unerupted teeth
impacted teeth
I. Full impaction vs. partial impaction
II. Orientation
- Vertical
- Inverted
- Mesioangular
- Distoangular
- Horizontal
- Inverted Mesioangular
- Inverted Distoangular
what is the orientation of impacted teeth needed for?
evaluate prognosis and surgical management
name this
inverted mesioangular impacted tooth
vertical partial impaction
vertical full impaction
Describe the impacted tooth
vertical distoangular full impaction
inverted mesioangular full impaction
horizontal full impaction
Problems with Supernumeraries
and Impacted Teeth
- Affect eruption of normal complement of teeth
- Cystic degeneration of follicular epithelium
enameloma
ectopic globule of enamel formation at the root surface
AKA enamel pearl
enameloma
dentinoma etiology
- may result from proliferation of conn tissue and hertwig’s epithelial root sheath cells
- epithelial remnants induce undifferentiated conn tissue cells to transform into odontoblasts and produce dentin
dentinoma
dentinoma
dentinoma
