common things occur commonly

09/01/2013
ERNEST LAM, DMD, MSc, PhD, FRCD(C)
Professor and the Dr. Lloyd & Mrs. Kay Chapman Chair in Clinical Sciences
Graduate Program Director and Head,
Discipline of Oral and Maxillofacial Radiology
Faculty of Dentistry, the University of Toronto
common things
occur commonly
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an incidental finding in a 47 year old female.
1
09/01/2013
mar 2003
nov 2002
oct 2004
?
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dense bone island

an asymptomatic, non-inflammatory hamartoma that
may or may not have an apparent association with
teeth.
 if there is an association, the tooth pulp is vital.
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09/01/2013
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dense bone islands are well-defined, noncorticated, radiopaque entities with borders
that blend into the adjacent normal trabecular
bone pattern.

in some instances when a dense bone island is
intimately associated with a tooth root, the root can
undergo external resorption.
 examples of this are most commonly seen in
mandibular first molars.
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most dense bone islands have the radiopacity of
cortical bone, however in some instances, they may
take on a more “ground glass” type of internal pattern.
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in these instances, these variants have also been
referred to as “subclinical fibrous dysplasia”.
▪ when this occurs, the periodontal ligament space
should remain intact, and the pulps of the affected
teeth remain vital.
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dense bone islands can also affect the deciduous
dentition.
dense bone islands require no treatment or
follow-up.
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70 year old female with an incidental finding on
a panoramic radiograph.
?
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dystrophic calcifications of the oropharyngeal
tonsils (tonsilliths).
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tonsilliths are well-defined, non-corticated
radiopaque masses that closely border or overly
the mandibular ramus.
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they often cast ghost images to the contra-lateral side
of the image.
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09/01/2013
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clinically, tonsilliths are cream-coloured entities that
resemble small stones.
▪ they may appear near the surface of the
pharyngeal tonsils, and be expelled spontaneously.
other dystrophic calcifications in the head and
neck:
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lymph node
sialolith
rhino/antrolith
calcified carotid atheroma
stylohyoid ligament (physiologic)
triticeous cartilage (physiologic)
calcified lymph nodes are typically seen
nearer to the angle of the mandible.
courtesy, DR. R. WITZKE
9
09/01/2013
a submandiublar duct sialolith seen
nearer to the angle of the mandible.
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an anthrolith in the right maxillary sinus.
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09/01/2013
carotid artery calcification (right) and stent (left).
courtesy, DR. B. PASS
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data supporting the hypothesis that
radiographically detectable CCAA is
associated with an increased risk of stroke are
incomplete and inconclusive.
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further research is needed, as clinical guidelines for risk
prediction using panoramic radiographs cannot be
established on the basis of the current evidence.
mupparapu and kim, jada 2007
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09/01/2013
bilateral stylohyoid ligament ossification.
incidental findings in the maxillary sinuses.
13
09/01/2013
?
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retention pseudocysts.
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although the etiology is still somewhat unclear,
retention pseudocysts are believed to arise from either
a blockage of seromucous secretory glands in the sinus
mucosa resulting in submucosal serous accumulations,
or cystic degeneration within an inflamed sinus lining.
retention pseudocysts are well-defined, noncorticated, dome-shaped radiopaque masses
that may be found in any of the paranasal
sinuses.
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retention pseudocysts are NOT mucoceles.
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incidental findings in the right maxillary molar area
in a 44 year old female.
?
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periapical osseous dysplasia.
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09/01/2013
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the osseous dysplasias are a group of bone
abnormalities that result in the deposition of a
fibrous connective tissue matrix mixed with
immature bone.

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the osseous dysplasias are well-defined,
radiopaque masses situated at or near the
apices of the teeth.
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of note is the fact that the histopathologic features of
these entities are virtually identical, not only to oneanother, but with other similar entities (e.g. fibrous
dysplasia, ossifying fibroma).
these radiopaque area are surrounded by radiolucent
borders or rims, and these in turn are surrounded by a
radiopaque border of variable thickness.
three stages have been described in the life of
the osseous dysplasias.
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an early stage, in which the lesions are primarily
radiolucent.
a mixed stage where a radiopaque focus may
be seen within the radiolucent area.
a mature stage, where the lesion is primarily
radiopaque.
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no treatment, including surgical manipulations
are required unless the lesions become
secondarily infected.
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supernumerary tooth (mesiodens, peridens,
distodens).
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it’s important to count teeth.
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given that most supernumerary teeth occur in
the anterior jaw, superimposition of the cervical
spine may make identification difficult.
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therefore, it is always prudent to make an intraoral radiograph of some variety.
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three-dimensional imaging may be helpful in
some cases to localize the positions of the
teeth.
8 year old female with supernumerary teeth.
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38 year old female referred for intermittent
swelling of the left cheek.
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09/01/2013
?
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dentigerous cyst.
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dentigerous cysts arise from the proliferation of the
reduced enamel epithelium lining the tooth follicle,
and by definition, they must be associated with the
crown of an unerupted tooth.
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09/01/2013
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dentigerous cysts are well-defined, variablycorticated, “hydraulic”, radiopaque entities
when they occur in the maxilla against the
background of an air-filled maxillary sinus.
it is also important to be able to assess the
association between the crown of the tooth
and the cystic area as the cyst should arise from
the CEJ area.
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09/01/2013
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if this association cannot be determined, the
possibility of other types of cysts must be
considered.
26
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buccal bifurcation cyst.
keratocystic odontogenic tumour
27
09/01/2013
keratocystic odontogenic
tumour.
dentigerous cyst.
keratocystic odontogenic
tumour.
dentigerous cyst.
35 year old male referred seeking
orthodontic treatment.
28
09/01/2013
?
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compound odontome.
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compound odontome.
complex odontome.
dilated odontome.
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09/01/2013
complex
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dilated odontoma.
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the dilated odontoma can be thought of as an “insideout” tooth, the extreme end of a spectrum of
invaginations that include dens invaginatus and dens in
dente.
30
09/01/2013
17 year old male with swelling in the anterior right maxilla.
31
09/01/2013
?
32
09/01/2013
rarefying osteitis (radicular abscess, radicular
granuloma, radicular cyst).
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rarefying osteitis is poorly- to moderately welldefined, radiolucent entity situated at the apex
of a tooth.
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in some instances, the periphery may be corticated,
while in other cases, the periphery may be noncorticated.
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