Inter radicular radiolucencies / dental courses

INTER RADICULAR
RADIOLUCENCIES
INDIAN DENTAL ACADEMY
Leader in continuing Dental Education
www.indiandentalacademy.com

 These are r/l that occur b/n the roots of the tooth.
 3 types:
1.Anatomic,
2.Pathologic- Related to tooth(odontogenisis)
Tumours of odontogenic origin
3. That could be develop anywhere in the skeleton
but chance occur in b/n roots of the tooth.
(neurofibroma).

Anatomic radiolucencies
1. Primary tooth crypts
2. Mental foramen
3. Shadow of maxillary sinus
4. Incisive foramen
5. Lateral fossa
6. Bone marrow patterns
7. Nutrient canals

Primary tooth crypts
 r/l seen in young children.
 The inter radicular ones represent
developing premolars, located b/n roots of
deciduous molars (2 yrs).

r/g of tooth crypts
commonly
Seen on primary
molars

Panoramic r/g showing primary tooth crypts

Mental foramen
o Small round r/l in the periapices of mandibular
premolar teeth.
o Occasionally in b/n roots of premolars.
o The mental foramen is the anterior limit of
the inferior dental canal
o The shape of the foramen may vary
round,oblong.slitlike.

r/g of mental foramen

shadow of Maxillary sinus
o It is an air containing cavity present in
maxilla
o The sinus may be considered as a three
sided pyramid
o It dips down b/n the molar tooth.
o Usually bilaterally similar.
o In some cases small buccal outpunching of the
sinus wall shows as a cyst like r/l b/n tooth
roots.

r/g of maxillary
sinus extends in
b/n tooth roots

Panoramic radiograph of
maxillary sinus

Shadow of incisive foramen
 Well defined contoured r/l b/n roots of
central incisors.
 Superior or inferior position may be
changed by vertical angulation.

r/g of incisive foramen

Lateral fossa
 Vertical depression present in labial
alveolar plate b/n lateral incisor and canine.

Bone marrow patterns
 Various shaped r/l patterns dispersed
through out alveolar bone, basal bone and
inter radicularly.

r/g of various bone marrow
patterns

Nutrient canals
 Nutrient canals carry neurovascular bundles
and appear as a radiolucent lines of fairly
uniform width .
 Vertical , narrow, band like r/l b/n tooth.
 X-ray beam is directed to long axis of
particular canal , nutrient canal is seen as a
small wormwhole.
 At times they orient in perpendicular to the
cortex and appear as a small round
radiolucency

r/g of nutrient canals

Pathologic radiolucencies
 Periodontal pocket
 Furcation
involvement
 Lateral radicular cyst
 Traumatic bone cyst
 Primordial cyst
 Odontogenic tumours
 Globulomaxillary r/l
 Incisive canal cyst
 Malignancies
 Lateral periodontal
cyst
 Median mandibular
cysts

Periodontal pockets
o Vertical bone loss, the r/l is inter radicular
but closer to involved tooth.
o Horizontal bone loss also produces r/l.

Various pattern of bone loss
producing r/l

Furcation involvement
 Advanced periodontal disease usually
produces furcation involvement.
 Usually periodontal probe can be
maneuvererd into furcation area.
 .

Advanced periodontitis
producing r/l

Lateral radicular cyst
Synonyms:Periapical cyst, apical periodontal
cyst, or dental cyst
 A radicular cyst is a cyst that most likely
results when rests of epithelial cells in the
periodontal ligament are stimulated by
inflammatory products from a nonvital
tooth.

 Radicular cysts are 3 types:
apical
lateral
It may occur when a accessory canal opens
into lateral root surface.

Panoramic view showing radicular cyst

Traumatic bone cyst
 Traumatic bone cyst, hemorrhagic bone
cyst, extravasation cyst, progressive bone
cavity, solitary bone cyst, or unicameral
bone cyst
 primarily involves the bone inferior to
apices of man premolars,1st molars and
extends up into area b/n these teeth.
In some cases primary involvement is inter
radicular bone.

r/g findings:
 Mandibular premolar to molar area.
 The margin may vary from a welldefined,
delicate cortex to an ill-defined border that
blends into the surrounding bone.
The shape most often is smooth and curved, like a
cyst, with an oval or scalloped border. The lesion
often scallops between the roots of the teeth.

the borders are ill defined and that
the lesion has scalloped around the
teeth

Primordial cyst(OKC)
 Noninflammatory odontogenic cyst that arises from
the dental lamina
 The most common location of an OKC is the posterior
body of the mandible (90% occur posterior to the
canines) and ramus (more than 50%) .
 The epicenter is located superior to the inferior
alveolar nerve canal.
 The cyst may have a smooth round or oval shape
identical to that of other cysts, or it may have a
scalloped outline.

OPG-showing primordial cyst with scalloping borders

OPG-showing primordial cyst

Odontogenic tumours
 Odontomas
 ameloblastoma

Panoramic r/g showing unilocular variety of
ameloblastoma

Panoramic r/g showing unilocular
variety of ameloblastoma

Globulomaxillary cyst
 Occurs in nests of epithelium in the fusion
line b/n maxillary process and globular
process of frontonasal suture.
 c/f:
asymptomatic,
the contact point b/n canine and lateral
incisor shifted incisally of teeth b/c rotation of
crowns by spreading of roots.

 Mucosa over buccal swelling is normal in
colour, on palpation produces crepitus if
cortical plate is still in contact, fluctuant if
not.
 On aspiration- typical ambered coloured
cystic fluid.

 r/g findings:
inverted pear or tear shaped r/l b/n
separated roots of lateral incisor and canine.
laminadura is intact.

Globulomaxillary cyst

 d/d:
odontogenic cyst
gaint cell granuloma
myxoma
AOT
surgical defect
anterior bony clefts

Incisive canal cyst
Synonyms: nasopalatine canal cyst, median
palatal cyst, median ant maxillary cyst.
embryonic odontogenic epithelium
remnants of nasopalatine duct undergo
proliferation and cystic degeneration.

c/f:
 Asymptomatic
 Small well defined swelling just post to
palatine papilla.
 If cyst expands penetrates labial plate.
 Lesion may also bulge into nasal cavity,
distort nasal septum.
 Burning sensation or numbness over
palatal mucosa.

r/g findings
Location:
 Antly max central incisors postly involve
hard palate.
 Destroying (expand) labial cortical bone
,tooth to diverge.
Periphery and shape:
 Well defined corticated.
 Shadow of nasal spine superimposition-
herat shaped.

Internal structure:
 Completely r/l.
Effects on surrounding structures:
 Roots of central incisors to diverge.
 Root resorption.
 Floor of nasal fossa may displaced superior
direction.
 Sometimes two separate cysts develop
simultaneously in the left and right sides and
cause paired like r/l.

d/d
 Large incisive foramen(rule of thumb-r/l of
incisive canal measuring less than 0.6cm in
diameter should not be considered cystic in
absence of other symptoms).
 Radicular cyst

Incisive canal cyst

Malignancies
 Begin at the interseptal bone and usually
present as r/l with poorly marginated
borders.

a.Metastatic malignancy
b.osteosarcoma

Lateral periodontal cyst(inflammatory)
 Pocket contents may be irritant that
stimulates adjacent rests of malaseez in the
PDL.

Lateral periodontal cysts

Lateral periodontal cyst(developmental)
 Unusual odontogenic cyst
 May be result from
 1.early dentigerous cyst left in place after
eruption of tooth.
 2.a primordial cyst
 3.rests of malaseez in PDL
 4.REE
 5.Remnants of dental lamina

c/f:
man canine and premolar area.
vital pulps
r/g:
 This condition usually is unicystic, but it may
appear as a cluster of small cysts, a condition
referred to as botryoid odontogenic cyst.
 Man lateral to 2nd premolar area
 Well defined r/l with cortical boundary.

Median mandibular cyst
 Symphyseal region of mandible.
 Originating from epithelium trapped in the
fusion or from merging of paired
mandibular processes.

Rare causes
 AOT
 Buccal cyst
 Langerhan’s cell disease
 Osteoradionecrosis
 Paradental cyst

a.Follicular
variant of AOT
b.Inter
radicular type
of AOT

Extra follicular variant of AOT

REFERENCES:
 Principles practice oral radiologic
interpretation H.m worth
 Oral radiology principles and
interpretation 5th edition white & pharaoh
 Differential diagnosis of oral and
maxillofacial lesions 5th edition norman.k
and wood,paul w.goaz

Inter radicular radiolucencies / dental courses

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (14)

Similar to Inter radicular radiolucencies / dental courses

Similar to Inter radicular radiolucencies / dental courses (20)

More from Indian dental academy

More from Indian dental academy (20)

Recently uploaded

Recently uploaded (20)

Inter radicular radiolucencies / dental courses