Definition
•Cyst is a pathological cavity that
may or may not be lined by
epithelium & usually containing
fluid or semi-fluid material.
Cysts of the
Oral cavity
True cyst Pseudocyst
True cyst is a pathological cavity lined by
epithelium & usually containing fluid or semi-fluid
material.
The epithelial lining may later degenerate under
certain conditions , but the cyst may have been
lined by epithelium at one stage of its
development.
Pseudocyst
are not lined by epithelium & may
or may not contain fluid or other
material.
Origin:
True cysts of the jaw & related tissues arise
from epithelial remnants of odontogenic or
non-odontogenic origin within the maxilla
& mandible.
A. Odontogenic Epithelium:
Odontogenic epithelium may be derived
from one of the following sources:
1. Possibly from cells of the basal layer of
the oral epithelium , from which the dental
lamina develops.
2. The dental lamina.
3. The epithelial rests of Serres , which
represent remnants of the dental lamina.
4. The enamel organ.
5. The reduced enamel epithelium remaining
on the surface of the crown after
completion of enamel formation ,
representing the remains of the enamel
organ.
6. The epithelial rests of Malassez ,
remnants of the epithelial root sheath of
Hertwig.
B. Non-Odontogenic Epithelium(Surface
secretory):
1.Epithelial cells remaining entrapped
between embryonic processes at the line
of fusion of these processes (fissural
cysts).
2. Epithelium from remnants of the cervical
sinus formed by overgrowth of the second
branchial arch over the succeeding
arches(i.e. Epithelium of branchial cleft
origin).
3. Secretory glandular epithelium of minor
mucous glands & of major salivary glands.
4. Remnants of the epithelium of the
vestigial nasopalatine duct.
5. Remnants of epithelium of thyroglossal
tract.
B. Other developmental Cysts:
1.Branchial cleft cyst (Benign lympho-
epithelial cyst of the neck).
2.Thyroglossal tract cyst.
3.Dermoid & Epidermoid cysts.
4.Heterotopic oral gastro-intestinal cyst.
III. Cysts of the salivary glands:
1.Mucous retention & extravasation cysts:
i.Mucocele.
ii.Ranula.
Pseudocysts:
1.Traumatic bone cyst (haemorrhagic bone
cyst; solitary bone cyst).
2.Aneurysmal bone cyst.
3.Static bone cyst (developmental salivary
gland inclusion cyst; latent bone cyst;
Stafne’s idiopathic bone cavity).
Classification by Tissue of
Origin
Derived from Rests of
Malassez
•Periapical cyst
•Residual cyst
Derived from Reduced
Enamel epithelium
•Dentigerous
cyst
•Eruption cyst
Derived from Dental
Lamina (Rests of
Serres)
Odontogenic
keratocyst
Gingival cyst of the
Newborn and adult.
Lateral periodontal
cyst.
Glandular odontogenic
cyst.
Unclassified
–Paradental cyst
–Calcifying
odontogenic cyst
Incidence of cysts of the jaws
•Radicular cysts 60-75%
•Dentigerous cysts10-15%
•Keratocysts 5-10%
•Paradental cysts 3-5%
•Nasopalatine cyst 5-10%
•Gingival, lateral periodontal, other non-
odontogenic and primary bone cysts1%
Cyst-like lesions:
I.Normal anatomical landmarks:
The following normal anatomical structures
produce a radiolucent picture that may
resemble the picture produced by a cystic
lesion:
1.Maxillary sinus.
2.Mental foramen.
3.Hemopoietic bone marrow defect &
physiologic osteoporosis.
4.Nasopalatine foramen & incisive canal.
II.Neoplastic & dysplastic lesions:
1.Odontogenic tumors such as simple
ameloblastoma, adenomatoid
odontogenic tumor, Pindborg’s tumor.
2.Pleomorphic adenoma of salivary glands.
3.Odontogenic myxoma & fibroma.
4.Giant cell lesions & tumors.
5.Fibrous dysplasia of bone & cherubism.
6. Central non-ossifying fibromas of the
jaws.
7. Early stage of cementifying fibroma.
8. Metastatic & invasive carcinomas to the
jaws.
9. Osteolytic osteogenic sarcoma.
10. Central hemangioma of the jaws.
III. Metabolic & Systemic Dysfunction:
1.Osteitis fibrosa cystica (hyperpara-
thyroidism, von Recklinghausen’s
disease of bone).
2.Langerhan’s Cell Reticulo-endothelioses:
a.Eosinophilic granuloma.
b.Hand-Schuller-Christan’s disease.
c.Leterrer-Siwe’s disease.
V. Periapical lesions:
1.Chronic periapical abscess.
2.Periapical granuloma.
3.Early stage(osteolytic stage) of periapical
cemental dysplasia.
4.Apical scar.
VI. Soft tissue benign tumors which may
appear clinically as cysts:
1.Soft fibroma.
2.Lipoma.
3.Myoma.
4.hemangioma,.
5.Lymphangioma.
DIAGNOSIS OF THE CYST
1.Physical signs.
2.Symptoms.
3.Radiographic examination.
4.Other radiological diagnostic techniques
5.Aspiration.
6.Biopsy.
Treatment of the cysts
Aim of treatment:
1-To remove the pathological epithelium
that forms the lining or to enable the
patient’s body to rearrange the position of
the abnormal tissue so that it’s eliminated
from within the jaw.
2-To do so with the minimum of trauma to
the patient, consistent with a successful
outcome to the operation.
3-To preserve adjacent important structures
such as nerves & healthy teeth.
4-To achieve rapid healing of the operation
site.
5-To restore the part to normal or near
normal form & to restore normal function.
Surgical Techniques
1-Enucleation or complete removal of the cyst
capsule & lining with its contents.
2-Marsupialization (Partch operation) by which the
cyst is uncovered or de-roofed by creating a
large opening in the bone & the cystic lining so
that the lining of the floor & walls becomes
continuous with the oral cavity epithelium & the
surrounding structures.
N.B:
Sometimes the lesion is initially treated by
marsupialization to decompress the intra-cystic
pressure until the cyst is reduced in size & then
a second operation is performed to enucleate
the cystic membrane.
Enucleation
Indications:
1-Accessible cysts.
2-Small to moderate sized cysts that don’t
extensively involve vital teeth or important
anatomical structures such as the maxillary
sinus & inferior alveolar bundle.
3-Cysts that don’t involve soft tissues.
Advantages:
1-Removal of the entire pathological tissue.
2-Rapid healing than that which occurs with
marsupialization.
3-Decreased need for post-operative care.
Disadvantages:
1-Large cysts may be technically difficult to
remove.
2-Possibility of damage to vital teeth.
3-Possibility of fracture of the mandible in large
cysts involving the lower jaw, also injury to
important anatomical structures could occur e.g.
inferior alveolar nerve & vessels.In large
maxillary cysts enucleation may lead to the
creation of an oro-antral communication with
subsequent effects on the maxillary
antrum;involvement of the floor of the nose may
also occur.
4-If the cyst extends to the soft tissues complete
removal may not be possible sometimes, with a
great possibility of recurrence.
Marsupialization
Indications:
1-Large cysts that are weakening the jaw.
2-Soft tissue cysts.
3-Cysts approximating vital teeth.
4-Cysts related to maxillary sinus or inferior
alveolar canal.
5-Dentigerous or eruption cysts to allow teeth to
erupt.
6-In elderly patients.
Advantages:
1-Preservation of vital structures from surgical
damage (teeth, maxillary sinus, inferior alveolar
nerve).
2-Minimizes bone removal ,thus the potential
danger of surgical fracture of the mandible is
avoided.
3-Bare bone is not exposed to infection.
4-Less traumatic procedure than enucleation,
hence less risky for poor surgical risk patients.
5-Needs less surgical skill than enucleation.
6-Preserves the normal contour of the mouth.
Disadvantages:
1-Leaves behind pathologic tissue with the
possible potentiality of change into malignant
neoplasm.
2-Slow healing.
3-Requires considerable post-operative care.
a.The defect is sometimes difficult for the patient
to keep clean during the healing period.
b.The defect doesn’t always fill completely with
bone.
Periapical Cyst
Most common odontogeniccyst
An odontogeniccyst of
inflammatory origin that is preceded
by a chronic periapicalgranuloma
and stimulation of rests of
Malassezpresent in the periodontal
membrane
Slowly progessive
painless swelling
with no symptoms.
size is variable but
usually less than 1
cm
If infected painfull
and rapid expansion
due to oedema.
Rounded swelling
and hard in the start.
Clinical features
When bone becomes
thin eggshell
crackling sound on
pressure
Finally, wall of cyst
resorbed leaving a
soft, fluctuent
swelling.
Bluish in color
beneath MM.
PATHOGENESIS
1-Proliferation of epithelial lining and
fibrous capsule.
2-Hydrostatic pressure of cyst fluid.
–Protein and infl. Exudate, also some high
mol. Wt. proteins -inc osmotic pressure
tension expansion of cyst in a balloon-
like fashion.
3-Resorption of surrounding bone.
Periapical Cyst
Radiographicallypresent as a
round to ovoid radiolucency
Apex of non-vital tooth
Less commonly between teeth –
lateral radicularcyst
Most are < 1.5 cm in diameter
Radicular cyst: ill-defined
lesion subjacent to carious
tooth root (arrow).
Radicular cyst: Note continuity between cyst cortex and
periodontal ligament space of grossly carious (C4) right
mandibular first molar. Cyst is a well-delineated
unilocular radiolucency. Note lower cortex expansion.
Radicular cyst on carious right
maxillary lateral incisor. The lesion
is a well-delineated unilocular
homogeneous radiolucency.
Radicular cyst on left mandibular first
permanent molar tooth. It is a well-delineated
homogeneous radiolucency.
Radicular cyst possibly of right mandibular
premolar tooth (or residual following extraction
of first molar) is a well-demarcated unilocular
homogeneous radiolucency (arrow).
Periapical Cyst
Variably thick, non-keratinized
stratified squamousepithelial
lining.
Prolifeartionassociated with ch
inflmay be thick, irregular and
hyperplasticor appear net-like,
forming rings and arcades.
Usually a significant degree of
inflammation present
Histological view
Cholesterol clefts (left by
fatty material)
Hyaline or Rushton
bodies seen.
Chronic inflammatory
cells (plasma cells,
lymphocytes, neutrophils,
macrophages in inner
wall)
Necrotic debris
Carious root fragment with nonvital pulp and
periapical cyst attached to apex.
B,The intraepithelial reddish-colored oval
and crescent-shaped structures that
occasionally are found are termed Rushton
bodies
Hyaline or Ruston Bodies
These are
translucent or pink-
staining lamellar
bodies formed by
the cyst lining epit.
And indicate
odontogenic origin
PERIAPICAL CYST
•Radiographic features
–Well-delineated
radiolucency
–Loss of the lamina dura
–Root resorption
–May become quite large
Periapical Cyst
Enucleation, with either
extraction or endodontic therapy
of the involved tooth
If the lesion is not removed, a
residual cyst may result
Recurrence is unlikely
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Cysts
RESIDUAL PERIAPICAL
CYST
A radicular cyst may persist after
tooth extraction.
Common cause of swelling of
edentulous jaw in older persons.
Thay are rare and can occasionally
form at site of a non-vital tooth as a
result of opening of a lateral branch
of root canal.
Well-defined radiolucency within the
alveolar ridge at the site of a
previous tooth extraction
RESIDUAL PERIAPICAL CYST
Histopathologic features
–Same as the periapical
cyst
Treatment
–Enucleation
Lateral Periodontal Cyst
(Botryoid Odontogenic Cyst)
A slow-growing, non-expansile
developmental odontogenic cyst
derived from one or more rests of
the dental lamina, containing an
embryonic lining of 1 to 3 cuboidal
cells thick.
Lateral Periodontal Cyst
Middle aged adults, males (2:1)
Asymptomatic, usually unilocular
radiolucency
Mandibular canine/premolar
region, < 1 cm
Lateral periodontal cyst:
unilocular well-corticated
radiolucency distal to
right mandibular canine.
L
Lateral periodontal cysts: bilateral lesions (rare
example) in mandible between canine and first
premolar teeth
Lateral periodontal cyst: well-delineated
multilocular (botryoid or “grape-like”)
homogeneous radiolucency between roots of left
mandibular premolar teeth.
Lateral Periodontal Cyst
Identical to gingival cyst of the
adult
Non-keratinized epithelium, focal
nodular thickenings, clear cells
Lateral periodontal cyst. A,Epithelial lining
consisting of cuboidal cells with occasional clear
cells. B,Lining containing focal thickenings (plaques
Histological features
1-3 squamous or cuboidal cell thick
clear cells filled with glycogen
peripheral zone of hyalinization
lack of inflammation cells
weak adherence to the surrounding
connective tissue
Dentigerous Cyst
Second most common odontogenic
cyst
A developmental cyst which arises
from the reduced enamel epithelium
and surrounds the crown of an
impacted tooth.
Dentigerous Cyst (Follicular
Cyst)
Formed by fluid accumulation between
the reduced enamel epithelium and the
enamel surface, resulting in a cyst in
which the crown is located within the
lumen and root(s) outside.
Dentigerous Cyst
Usually detected in young adults
20-50 years
Male : female ratio 2:1
Usually not clinically visible without
radiographs
Asymptomatic until swelling appears.
Clinical Features:
Occasionally pain or swelling
Firm hard mass
Appears as if missing a tooth
Usually involve unerupted
mandibular third molars, other
frequent sites include maxillary
canines, maxillary third molars and
mandibular second premolars
DENTIGEROUS CYST
•Radiographic features
–Unilocular radiolucency
associated with the crown of an
unerupted tooth
•Central variety
•Lateral variety
•Circumferential variety
–Radiolucency should be at least
3-4 mm. in diameter
Dentigerous Cyst
Thin, non-keratinized stratified
squamous epithelial lining
Connective tissue wall is usually
uninflamed, although secondary
inflammation may be present
Mucous cells may also be seen in
the cyst lining
Histologic Features:
uniform few (2-5) cells thick nonkeratinized,
stratified squamous epithelium lining
epithelial lining may be hyperplastic, atrophic
or ulcerated
acute or chronic inflammatory cells
crystalline cholesterol deposits
hemosiderin deposits
hyaline (Rushton) bodies
lipid-laden macrophages
mucus cells in epith. lining
Histologic Features
Dentigerous cyst.Lining exhibiting a thin
stratified squamous epithelium without rete peg
formation and a capsule of dense fibrous
connective tissue
Dentigerous cyst seen as well-delineated
homogeneous radiolucency surrounding crown
of distally inclined third mandibular molar.
R
Dentigerous cyst: expansile unilocular
homogeneous radiolucency attached at
enamel-cemental junction of right molar.
R
Dentigerous cyst: left mandubular ramus.
well-demarcated, unilocular homogeneous
radiolucency envelopes third molar tooth.
Dentigerous cyst: well-delineated radiolucency
Surrounding and displacing in left mandibular
canine causing displacement and root resorption
of adjacent teeth.
Dentigerous cyst:
axial CT from previous
patient. Note buccal and
lingual expansion of
mandible.
R
Dentigerous cyst: 0.5
Tesla,T2-weighted MRI
image of same patient.
Note high signal intensity
of cyst contents.
Dentigerous cyst: well-
delineated unilocular
homogeneous radiolucency
displacing left maxillary
third molar.
DENTIGEROUS CYST
Treatment
–Enucleation with
removal of the
unerupted tooth
–Marsupialization
ERUPTION CYST
(ERUPTION HEMATOMA)
ERUPTION CYST
•Soft tissue analoque of the
dentigerous cyst
•Swelling of the gingival mucosa
overlying the crown of an erupting
deciduous or permanent tooth;
usually the first permanent molars
or maxillary incisors
•Children < 10 years of age
ERUPTION CYST
•Lies Superficial in the gingiva, overlying
the unerupted tooth.
•Appears as a soft, rounded, and bluish
swelling.
•Eruption hematoma:
•Blood accumulates in the cystic fluid
Histologic Features
•lined by a thin layer of non-keratinizing
squamous epithelium
•inflammatory cells may be present
•red blood cells and exfoliated ghost
cells in the lumen
ERUPTION CYST
•Treatment
–Excision of the roof
of the cyst to permit
eruption
Primordial Cyst
By definition, a developmental
odontogenic cyst that arises in
place of a tooth, usually a mand.
3
rd
molar
Should be no history of
extraction of a tooth in the area
Most are OKC’s microscopically
Primordial Cyst
The overwhelming majority of these
cysts prove to be odontogenic
keratocysts on microscopic
examination
Thin, uniform lining that produces
parakeratin and exhibits palisading
of the basal cell layer
Treatment
Essentially the same treatment
that is rendered for the OKC
Enucleationand curettage for
small, unilocular lesions
More aggressive therapy for
larger, multilocularlesions
Odontogenic
Keratocyst
Benign but locally aggressive
developmental odontogeniccyst
Probably arises from dental lamina
rests
Affects a wide age range, beginning
in the second decade of life (20-70)
Asymptomatic until swelling
develops
Odontogenic
Keratocyst
Most commonly seen in the
posterior mandible, but any
segment of the jaws can be affected
–clinically may mimic a wide
variety of jaw cysts
Unilocular radiolucency when small
Multilocularappearance often
develops as the lesion enlarges
Pathogenesis
These cysts have insidious patteren of
growth.
They don’t have internal pressure like
radicular cysts,and expand along the
medullary cavity, the path of least
resistance.
So they expand along the body and
ramus of mandible without causing
much jaw expansion except in
advanced lesions.
ODONTOGENIC
KERATOCYST
•Radiographic features
–Unilocular or multilocular
radiolucency
–Well defined radiolucent areas,
with rounded or scalloped
margins.
–25-40% associated with an
unerupted tooth
•Root resorption is less common
compared to the dentigerous cyst.
•Roots of adjacent teeth may be
displaced by large cysts but usually
cysts expand around the roots and
ID canal without displacing them or
causing expansion.
•An odontogenic
•keratocyst in the left
•body and ramus of
•the mandible and
•appearing as a large
•solitary
radiolucency.
•An odontogenic
•keratocyst having a
•multilocular
•appearance. It
•should be
•differentiated from
•other multilocular
•lesions.
R
Odontogenic keratocyst:
unilocular homogeneous
radiolucency in right
mandibular ramus
(detail from panoramic
radiograph).
L
Odontogenic keratocyst:
large crenulated
homogeneous radiolucency
enveloping third molar tooth
in left mandibular ramus.
Odontogenic keratocyst: multilocular
homogeneous radiolucency in left mandibular
body is well demarcated with little expansion.
Odontogenic keratocyst:
detail from panoramic
radiograph showing
homogeneous radiolucency
that surrounds roots of right
premolar and molar. The
definitive diagnosis awaits
histopathology in such cases.
Odontogenic keratocyst
(true occlusal radiograph):
homogeneous radiolucency
without expansion of the
buccal plate of the mandible.
Odontogenic
keratocyst: note
lack of jaw expansion
and lack of tooth
resorption by this
large well-delineated
homogeneous
radiolucency crossing
the midline of the
mandible
(topographic occlusal
view).
R
Odontogenic keratocyst: PA radiograph
showing multilocular radiolucency in right
side of mandible. Expansion as seen in this case
is a late feature of this disease process.
Odontogenic keratocyst: panoramic view of
lesions in both jaws from multiple nevoid basal
cell carcinoma syndrome.
Odontogenic keratocyst:
unilocular homogeneous
radiolucency lesion that
does not cross the midline
(distinguishing it from the
nasoplaatine duct cyst) and
causes neither resorption
nor marked displacement of
adjacent teeth.
R
Odontogenic keratocyst
(recurrent): well-delineated
multilocular homogeneous
radiolucency lesion (arrow)
at right mandibular angle.
Unlike most odontogenic
lesions this case did extend
below the mandibular canal.
Odontogenic
Keratocyst
•Uniform, thin stratified squamous
epithelial lining
•Luminal parakeratinproduction
•Palisaded(“picket fence”)
appearance of the basal cell nuclei
•Flat lower border of epith.
•Satellite cyst formation may be seen
in Connective tissue.
Odontogenic keratocyst.Low (A)and high (B)magnification of thin epithelial lining (6
to 10 cells) exhibiting the keratin-filled lumen, corrugated parakeratinizing
surface, and palisaded basal cell layer that lacks rete peg formation and
displays a delicate, loose connective tissue capsule. C,Capsule wall containing
satellite (daughter) cysts.
Histological features
•usually not inflammed
•distinct basal columnar cells
•space between epithelial tissue and
fibrous connective tissues
•no retepegs
•corrugated outer epithelial layer (6-10
rows of cells)
•Features altered with inflammation,
epith lining shows hyperplasia,
resembling to radicularcyst.
Reasons for recurrence of
OKC
•33% recurrence rate overall due to:
•Thin, fragile lining difficult to enucleate.
•Finger-like cyst extension into
cancellousbone.
•With occurrence in the first decade,
•With multiple OKC’s, the nevoid basal
cell carcinoma syndrome.
•Possibly a neoplasm.
Reasons for recurrence of
OKC
•Satellite (daughter) cysts in wall
•More rapid proliferation of keratocyst
epithelium.
•Formaion of additional cyst from other
dental lamina remnants (pseudo-
recurrence).
•Inferior surgical treatment
ODONTOGENIC
KERATOCYST
•Treatment and prognosis
–Enucleation, curettage, or
peripheral ostectomy
–Multiple recurrences are not
unusual; often 5-10 years after
the initial surgical procedure
•Nevoid basal cell carcinoma syndrome.
Features include calcification of the falx cerebri
(A),forehead exhibiting frontal bossing with skin
“milia” (B),and shortened metacarpals (C).
Nevoid basal cell carcinoma syndrome.
Reveals multiple odontogenic keratocysts.
Lesions are present in the posterior of all four
quadrants with displaced unerupted molars
GORLIN SYNDROME
•Autosomal dominant trait
•Multiple basal cell carcinomas of the
skin, multiple OKC’s, rib and vertebral
anomalies, and intracranial
calcifications
•40% of patients have ocular
hypertelorism
GORLIN SYNDROME
•Basal cell carcinomas
–2nd-3rd decades of life
–Occur on the midface area and on
non-sun exposed skin
•Palmar and plantar pits
–Occur in 65% of patients
–Represent a localized retardation
in the maturation of basal
epithelial cells
GORLIN SYNDROME
•Skeletal anomalies(rib and vertebrae)
–Occur in 60%-75% of patients
–Bifid ribs or splayed ribs
–Lamellar calcification of the falx
cerebri
–Cleft lip and palate (5% cases)
•Odontogenic keratocysts
–Occur in 75% of patients
–Occur at an earlier age than isolated
OKC’s
–Often multiple
Facial Asymmetry-Gorlan’s
Syndrome
•Intracranial
•calcifications in
basal
•cell nevus
syndrome.
•Calcification of falx
•cerebri in basal cell
•nevus syndrome.
Nevoid BCCa Syndrome
•Sun screens
•Excision of basal cell
carcinomas as needed
•Monitor for and excise OKCs
•Genetic counseling
Paradental Cyst
•A cyst of odontogenic origin commonly
located subgingivally on the buccal
aspect of an erupted mandibular molar
(bifurcation) or the distal surface of a
partially erupted mandibular third molar.
•When located on the buccal aspect of a
molar (usually 1
st
or 2
nd
) overlying the
bifurcation area and upper portion oif
the root, it has been termed as buccal
bifurcation cyst or less commonly a
Craig cyst.
•Believed to arise from reduced enamel
epithelium (sulcular epith).
•A significant feature for many such
cysts is that associated tooth exhibits an
anomaly as cervical enamel projection.
•Once cyst formation starts, it extends
apically below the CEJ into the
bifurcation area and beyond.
•Presence of cyst and inflammation in
such superficial intraoseouslocation in
young patients may induce a reactive
periosteal proliferation or localized form
of Garre’sosteomyelitis which resolves
when cyst is removed.
Glandular Odontogenic Cyst
•More recently described (45 cases)
•Gardner, 1988
•Mandible (87%), usually anterior
•Very slow progressive growth (CC:
swelling, pain [40%])
•Radiographic findings
–Unilocular or multilocular radiolucency
Glandular Odontogenic Cyst
•A,Glandular odontogenic cyst
presenting as a well-circumscribed
radiolucency in the posterior mandible
of a 69-year-old male. B,Thin lining
exhibiting cuboidal and columnar cells
with intraepithelial microcysts containing
mucoid secretion.
Glandular Odontogenic Cyst
•Histology
–Stratified epithelium
–Cuboidal, ciliated
surface lining cells
–Polycystic with
secretory and
epithelial elements
Treatment of GOC
•Considerable recurrence potential
•25% after enucleation or curettage
•Marginal resection suggested for larger
lesions or involvement of posterior maxilla
•Warrants close follow-up
Gingival Cyst of the
Newborn
•Derived from dental lamina rests
•1-2 mm whitish papules on
alveolar ridge mucosa in
newborns, maxilla
•No treatment needed
Gingival Cyst of the
Newborn
•Similar inclusion cysts are
found near midline palatal raphe
(Epstein’s pearls) or more
laterally along hard and soft
palate (Bohn’s nodules)
•Dental lamina cyst of the newborn.
•A,Multiple white lesions of maxillary
ridge of infant.
•B,Microscopic appearance exhibiting
several small keratin-filled cysts located
close to the overlying oral epithelium
Palatal Cysts of the Newborn
(Epstein’s Pearls, Bohn’s Nodules)
•As palatal shelves fuse to form secondary
palate, small islands of epithelium may become
trapped below surface
•Or may arise from epithelial remnants from
development of minor salivary glands
•Epstein’s pearlsoccur along median palatal
raphe
•Bohn’s nodulesare scattered over the hard
palate.
•No treatment required –self-healing
Gingival Cyst of the
Adult
•Derived from dental lamina rests
•Middle-aged adults (5th-6th
decades)
•Mandibular canine/premolar
region most common
•Bluish-translucent swelling,
often centered in attached
gingiva
Gingival Cyst of the
Adult
•Thin, non-keratinized cuboidal to
stratified squamous epithelium
•Occasional clear cells
•Nodular thickenings of epithelial
lining may be seen
•Gingival cyst of the adult.Small lesion
of gingiva (A)with lining containing focal
thickening (plaque) similar to lateral
periodontal cyst (B).
GINGIVAL CYST OF THE
ADULT
•Treatment and
prognosis
–Surgical excision
–Prognosis is
excellent
Calcifying Odontogenic
Cyst
•Also known as the Gorlin cyst
•Most common in 2nd-3rd
decades, but wide age range
seen
•Anterior portions of jaws (65%)
•Usually intrabony, but peripheral
lesions make up 13-30%
Calcifying Odontogenic
Cyst
•Radiographically: defined
unilocular radiolucency +/-
variable radiopacities
•Resorptionand divergence of
adjacent roots often seen
•1/3rd present with impacted tooth
•20% present with odontoma
CALCIFYING
ODONTOGENIC CYST
•Radiographic features
–Presents as a well-defined
unilocular or multilocular
radiolucency
–1/3 to 1/2 of cases are associated
with radiodensities
–1/3 of cases are associated with an
impacted tooth, often a canine
Calcifying odontogenic
Cyst:
“salt and
pepper”
calcifications
within an
expansile
unilocular
otherwise lucent
lesion (true occlusal)
Calcifying Odontogenic
Cyst
•Cystic epithelial lining with
resemblance to ameloblastoma
(peripheral columnar cells and
stellate reticulum-like areas)
•Variable numbers of ghost cells
and dystrophic calcifications
•Microscopic features reveal a thick
epithelial layer lining a cystic space
consisting of palisaded columnar basal
cells, accumulations of enlarged
eosinophilic epithelial cells without
nuclei (ghost cells), and spherical
calcifications.
CALCIFYING
ODONTOGENIC CYST
•Treatment and
prognosis
–Enucleation
–Prognosis is good
NONODONTOGENIC CYSTS
1. CYST OF THE VESTIGIAL DUCT
•Nasopalatine duct cyst
•Nasolabial cyst
•GLOBUULLOMAXILLARY CYST
•MEDIAN PALATAL CYST.
2.CYST OF THE VESTEGIAL TRACT
•Thyroglossal cyst
•Lymphoepithelial cysts
3.CYSTS OF THE EMBRYONIC SKIN
•Dermoid cyst
•Epidermoid cyst
Nasolabial Cyst(Nasoalveolar Cyst)
•Nonpainful swelling of upper lip lateral to midline,
resulting in elevation of ala of nose
•May result in nasal obstruction or may interfere
with denture.
•May rupture and may drain into oral cavity or
nose
•Complete surgical excision is preferred treatment
Nasolabial cyst
•A developmental cyst of the soft tissue
of the anterior muco-buccal fold
beneath the ala of the nose, most likely
derived from remnants of the inferior
portion of the nasolacrimal duct.
Nasolabial cyst: note displacement of
ala on right side.
Clinical features
•black female
predilection
•4th and 5th decades of
life
•usuallly unilateral
•asymptomatic soft
tissue swelling
•most are less than 1.5
cm
•occurs in the region of
the maxillary lip and
alar base, lateral to the
midline
Nasolabial cyst: lateral view shows antero-posterior
dimensions of contrast-enhanced cyst.
Histological features
•lined by a layer of
pseudostratified columnar
epithelium (respiratory
epithelium) stratified
squamous epithelium or a
combination of these
•mucus filled goblet cells
may be scattered within
the epithelium
•fibrovascular stroma
•inflammatory cells may
be present
•
•
•Nasolabial cyst.
Microscopic features
exhibiting loose
connective tissue
surrounding a lumen
lined with ciliated
pseudostratified
columnar epithelium
containing mucus
(goblet) cells
Nasopalatine Duct Cyst
(Incisive Canal Cyst)
•Most common non-odontogenic cyst of oral
cavity
•Canals of Scarpa, organs of Jacobson
•Presenting symptoms include swelling of interior
palate, drainage and pain
•Well circumscribed radiolucency in or near the
midline of the anterior maxilla between and apical
to the central incisor teeth
Nasopalatine duct cyst
causing palatal expansion,
a common finding.
Nasopalatine duct cyst
less frequently causes
sublabial swelling.
Nasopalatine duct cyst: a well delineated
ovoid unilocular radiolucency in the midline of
the maxilla. The teeth are all vital. (topographic
occlusal view).
Nasopalatine duct cyst:
Well-delineated
unilocular radiolucency
in the midline of the
maxilla. Adjacent teeth
are vital.
Nasopalatine duct cyst:
large unilocular
radiolucency occupies much
of the palate and is causing
tooth displacement
(topographic occlusal view).
HISTOLOGICAL FEATURES
•Stratified squamous
epithelium, or ciliated
columnar epithelium
or at times both.
•Mucous gland in the
wall.
•Small arteries and
nerves are present in
tne connective tissue.
•Nasopalatine duct
cyst.A cyst lined by
respiratory-type
epithelium
surrounded by a
fibrous capsule
exhibiting a mild
degree of chronic
inflammation
DIFFRENTIAL DIAGNOSIS /
MANAGMENT
•Peri apical
granuloma
•Radicular cyst
•Enucleation
•Marsupilization
for the larger
cysts
Incisive Canal Cyst
•Derived from epithelial remnants of the
nasopalatine duct (incisive canal)
•4
th
to 6
th
decades
•Palatal swelling common, asymptomatic
•Radiographic findings
–Well-delineated oval radiolucency between
maxillary incisors, root resorption occasional
•Histology
–Cyst lined by stratified squamous or
respiratory epithelium or both
Mar 13th, 2007 277
Incisive Canal Cyst
Incisive Canal Cyst
Incisive Canal Cyst
•Treatment consists of surgical
enucleation or periodic radiographs
•Progressive enlargement requires
surgical intervention
Globulomaxillary Cyst
•Well-circumscribed unilocular radiolucency
between and apical to the teeth resembling an
inverted pear
•Some are consistent with periapical cysts, some
have features of odontogenic keratocyst, or
developmental lateral periodontal cyst
•Treatment consists of surgical enucleation,
endodontic therapy
•Globulomaxillary
cyst
•showing the
•characteristic
inverted
•pear-shaped
•appearance. The
•adjoining teeth are
•vital.
Median Palatal Cyst
•True median palatal cyst presents as firm or
fluctuant swelling of the midline of the hard
palate posterior to the palatine papilla
•Well circumscribed radiolucency in the midline of
the hard palate
•Treatment is surgical removal
Median palatal cyst
•Occurs in the midline of posterior
palate.
•Is considered to be a distal
growth/extension of nasopalatine cyst.
•Present within the palate giving a
radiolucent appearance.
•Can be of variable size affecting palate.
Median Mandibular Cyst
•Most of odontogenic origin
•Midline radiolucency found between or
apical to the mandibular central incisor
teeth, cortical expansion
•Treatment is surgical enucleation
•Median mandibular
•cyst is a very rare
•cyst. The
•radiolucency
(arrows)
•between the two
•central incisors is a
•median mandibular
•cyst.
Dermoid and Epidermoid Cyst
•A cyst of the midline of the upper neck or the
anterior floor of the mouth of young patients,
derived from remnants of embryonic skin,
consisting of a lumen lined by a keratinizing
stratified squamous epithelium and containing
one or more skin appendages such as hair,
sweat, or sebaceous glands.
•If no skin appendages (hair, sweat and
sebaceous glands) are present, it will be
termed as epidermoid cyst.
Epidermoid Cyst
of the Skin
•Nodular, fluctuant, subcutaneous lesions that
may or may not be associated with inflammation
•Most common in the acne-prone areas of the
head, neck, and back
•May be associated with Gardner syndrome
•Treatment is conservative surgical excision
•Microscopic appearance
of cyst wall reveals a
lumen lined by stratified
squamous epithelium
with a thickened layer of
orthokeratin and a
connective tissue
capsule devoid of skin
appendages.
Dermoid Cyst
•Benign cystic form of teratoma
•Teratomais a developmental tumor composed of
tissue from ectoderm, mesoderm, and endoderm.
•In most complex form, teratomatous
malformations produce multiple types of tissue
arranged in a disorganized fashion
Dermoid Cyst, cont.
•Teratoid cyst–cystic form of teratoma that
contains a variety of germ layer derivatives (skin
appendages, connective tissue elements, and
endodermal structures)
•Dermoid cysts are simpler in structure
than complex teratomas or teratoid cysts
Dermoid Cyst, cont.
•Occur in midline of floor of mouth.
•Usually slow growing and painless, presenting as
a doughy or rubbery mass that retains pitting
after application of pressure
•Secondary infection may occur, treatment is
surgical removal
Dermoid cyst
Neck: dermoid cyst
Clinical features
•asymptomatic and
slow growing young
adults usually
midline of neck or
floor of mouth less
than 2 cm soft upon
palpation
•
•
•A,Dermoid cyst in this 18-year-old
female is located between the
mylohyoid muscle and present as a
subcutaneous swelling below the chin.
B,Cyst lumen is lined by an
orthokeratinizing stratified squamous
epithelium with hair follicle, sebaceous
glands, and sweat glands in the capsule
Thyroglossal Duct Cyst
(Thyroglossal Tract Cyst)
•60%-80% of cysts develop below hyoid bone
•Usually presents as painless, fluctuant, movable
swelling unless complicated by secondary
infection
•Best treated by removal of cyst, midline section
of hyoid bone, and muscular tissue
THYROGLOSSAL CYST
“a cyst of the vestigial tract”
•It is derived from the residues of the
embryoniv thyroglossal duct .
•As embryonically the glands desends
from the foraman caecum of the tongue
the residues usually get entrapped in
the region of the hyoid bone where it
can give rise to the cyst
•Sites like floor of the mouth and the
tongue are very rare
•Management : surgery
Thyroglossal Cyst
•Midline mass
•Age 10 –20yrs
•Most common cystic embryological
remnant in head/neck
•65% infrahyoid
•Elevate on protrusion of tongue
Microscopic features reveal
thyroid tissue in cyst wall
THYROGLOSSAL CYST
/contd
Cervical Lymphoepithelial
Cyst(Branchial Cleft Cyst)
•Developmental cyst that occurs in upper lateral
neck along anterior border of the
sternocleidomastoid muscle
•Soft fluctuant mass ranging from 1-10 cm
•Increased numbers reported in persons with HIV
infection
•Treatment is surgical removal
A portion of the cyst wall lined by keratinizing squamous
epithelium and containing lymphoid tissue.
Lumps
What can you describe?
•Site
•Size
•Shape
•Surface
•Edge
•Consistency
•Colour
•Transillumination
Fixation / tethering
•Pulsation
Thyroid Lumps
•Goitre
•Single nodule
•Multiple nodules
•Elevate on swallowing
•May have features of hyper / hypothyroidism
•Eye signs
•Rarely midline
Carotid Body Tumour
•Slow growing
•Carotid bifurcation
•Transmits carotid pulse
•May be pulsatile itself
•Moves side –side, not up –down
Parotid Tumours
•Pre and post auricular
•May elevate earlobe
•May involve facial nerve
Summary list of lumps
•Thyroglossal cyst
•Dermoid cyst
•Thyroid lump
•Carotid body tumour
•Lymph node
•Parotid tumour
•Elevates when tongue out
•Midline, fixed to skin
•Elevates on swallowing
•Pulsatile, side –side mvmt
•Lifts earlobe
Oral Lymphoepithelial Cyst
•Waldeyer’s ring–palatine tonsils, lingual
tonsils and pharyngeal adenoids
•Small asymptomatic submucosal mass,
firm or soft, white or yellow, on floor of the
mouth
•Treatment is surgical excision
Oral lymphoepithelial cyst.
Lesion of floor of mouth
A,Low magnification of photomicrograph
of keratin-filled cyst surrounded by
lymphoid follicles from the anterior floor
of the mouth.
•B,Higher magnification exhibiting a
thinned squamous epithelium, keratin in
the lumen, and surrounded by a dense
zone of lymphocytes
Pseudocysts
Mar 13th, 2007 323
Salivary Gland
Inclusion Defect
Stafne Defect
Mar 13th, 2007 324
Stafne Defect
Mar 13th, 2007 325
Stafne Defect
Mar 13th, 2007 326
Stafne Defect
Stafne Bone Cyst
•Submandibular salivary gland depression
•Incidental finding, not a true cyst
•Radiographs –small, circular, corticated
radiolucency below mandibular canal
•Histology –normal salivary tissue
•Treatment –routine follow up
Stafne Bone Cyst
Stafne bone cavity
•Stafne bone cavity
•is a well-defined
•cyst-like
•radiolucency with a
•radiopaque border.
•Its characteristic
•location is near the
•angle of the
•mandible, inferior to
•the mandibular
•Stafne bone cavity
near the angle of the
mandible, inferior to
the mandibular
canal.
•(in edentulous
patient)
Traumatic Bone Cyst(simple
bone cyst / solitary bone cyst)
•Empty or fluid filled cavity associated
with jaw trauma (50%)
•Radiographic findings
–Radiolucency, most commonly in body or
anterior portion of mandible
•Histology –thin membrane of fibrous
granulation
•CLINICAL FEATURES
•Most common in long bones and rare in
jaws.
•Occurs in children and adolescents
•2-3
rd
decade slightly higher ratio for
males.
•Site: premolar and the molar region in
the mandible.
•Majority of the lesions are
asymptomatic.
Traumatic Bone Cyst
Traumatic bone cyst, also known as simple
bone cyst, exhibiting the Characteristic
scalloping between the roots of the
mandibular anterior teeth.
Traumatic bone cyst extending from right
premolar to left canine (mandibular true occlusal
view). Note lack of expansion.
Traumatic bone cyst: axial CT shows only minor
expansion of mandible in molar region (arrow).
Traumatic bone cyst
Normal follicle
space.
Lesion.
Traumatic bone cyst showing
typical scalloped appearance
from extension between tooth
roots. Note partial loss of
lamina dura.
Traumatic bone cyst in
mandibular premolar
region (detail from
panoramic radiograph).
This is a well-delineated
noncorticated lucency.
HISTOPATHOLOGY
•Surgical exploration confirms the diagnosis.
•Consists of a rough bone cavity devoid of any
lining or epithelium
•The cavity may be empty or contains clear
blood or stained fluid
•Bony wall is covered with delicate loose
vascular fibrous tissue
•The tissue containing extravasated red blood
cells and hemosidrin pigments
•No histological evidence of any epithelial
lining
•A, Photomicrograph of active lesion reveals a
thinned CT lining surrounding a lumen that contains
a thin layer of fibrin on the luminal surface and
deposits of hemosiderin.
•B, In areas in which healing has begun, the tissues
display a distinctive lamellar pattern of mineralization
and new bone formation within the regenerating
connective tissue.
MANAGEMENT
•Curettage ---exploratory surgery may
expedite healing
Aneurysmal Bone Cyst
•etiology is unknown it may be due to
failure of attempted repair of a
haematoma in bone in which a
circulatory connection with the damaged
vessels persists leading to a slow flow
of blood through the lesion
ANEURYSMAL BONE CYST
•Rare cyst of the jaws
•Site: post, ramus region of the mandible
•Radiograph: uni or multilocular with
ballooned out appearance due to cortical
plate expansion
•Histopathology: blood filled endothelial
spaces separated by cellular fibrous
tissue,there is presence of multinucleated
giant cells.
MANAGEMENT
•Surgical curettage
•Aneurysmal bone
cyst
•in the anterior region
•of the mandible
•exhibiting internal
•septa.
•Aneurysmal bone
cyst producing
expansion of the
cortical plates.
R
Aneurysmal bone cyst:
PA view
showing buccal
expansion in left
mandibular angle.
Aneurysmal bone cyst: PA view of lesion in right
mandibular ramus, the most common site for this
condition in the jaws (more than 99% of this lesion
are found elsewhere in the skeleton).
R
ANEURYSMAL BONE CYST/
contd
•Microscopic appearance reveals multiple
sinusoidal spaces without an endothelial cell
lining, separated by cellular fibrous septa,
containing fibrohistiocytic cells and islands of
bone formation. Some lesions also will contain
foci of multinucleated giant cells.
Surgical Ciliated Cyst
•May occur following Caldwell-Luc
•Trapped fragments of sinus epithelium
that undergo benign proliferation
•Radiographic findings
–Unilocular radiolucency in maxilla
•Histology
–Lining of pseudostratified columnar ciliated
•Treatment -enucleation