Odontogenic cysts and tumors
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• Gorlin’s syndrome and OKC : basal cell nevus
syndrome
• Solid ameloblastoma without cortical bone perforation :
excision with bony margin 1 cm
• Radiographic feature of benign odontogenic cyst and
tumor
• Multiple osteoma maybe Gardner syndrome
:
familial adenomatous polyposis (FAP) with the extracolonic
manifestations of intestinal polyposis, desmoids, osteomas, and
epidermoid cysts (ie, Gardner syndrome).
Odontogeneis
Primitive oral cavity : stomodeum
develop from breakthrough of buccopharyngeal
membrane , lined with ectoderm
: ectomesenchyme = tissue of tooth develop
Tooth bud 3 parts
1. Enamel organ : tooth enamel
2. Dental papilla : tooth pulp + dentin
3. Dental sac
: cementum + periodontal ligament
Odontogenesis
Tooth development : 4 stages
1. Dental lamina stage
2. Bud stage
3. Cap stage
4. Bell stage
* Bud,Cap,Bell,Crown
•Interruptions in this sequence may lead to the
formation of odontogenic tumors.
Dental lamina stage
• About 6 weeks old
– Ridge of basal cell along oral ectoderm
proliferation
– Form band of epithelium : dental lamina
( future = dental arch )
Bud stage
• Epithelial downgrowth and proliferation
invagination into ectomesenchyme
• Represent the beginning of tooth development
appearance of a
tooth bud
without a clear
arrangement of
cells
A: Epithelial downgrowth
along the dental lamina in the
upper and lower jaws.
B: A magnified view of the
bud stage of development.
Cap stage
• The first signs of an
arrangement of cells in the
tooth bud occur
The peripheral cells are
cuboidal  the outer
enamel epithelium (OEE)
The cells in the concavity are
tall columnar cells  inner
dental epithelium.
Bell stage
• The histodifferentiation
and morphodifferentiation
takes place
A = enamel
B = dental papilla
C = dental follicle
Crown stage
• Maturation stage
• Hard tissue formation
– Enamel
– Dentin
– Cementum
• Forming
– Odontoblast
– ameloblast
Definition : Odontogenic
• Derived from tooth forming structure
Formation of odontogenic cyst and tumor
Derived from :
(1) the reduced enamel
epithelium of the tooth
crown
(2) epithelial rests of
Malassez, which are
remnants of the Hertwig
root sheath
(3) epithelial rests of
Serres, which are
remnants of the dental
lamina
(4) the tooth germ itself,
which includes the
enamel organ, dental
papilla, and dental sac
Diagnosis
• Complete history
– pain, loose teeth, recent occlusal problems,
delayed tooth eruption, swellings, dysthesias
or intraoral bleeding
– onset and course of the growth rate of a mass
– parasthesias, trismus, and significant
malocclusion
Don’t forget : many of these lesions are associated with
impacted or congenitally missing teeth
• physical examination
–
careful inspection, palpation, percussion and
auscultation of the affected part of the jaw and
overlying dentition
buccal expansion resulting
from growth of an
odontogenic tumor in the
body of the mandible
(arrows).
• A panorex radiograph will often confirm
clinical suspicions
– well-demarcated lesions outlined by sclerotic borders
suggest benign growth
– ill-defined lytic lesions with possible root resorption :
malignancy
DDX
•
By radiographic presentation
( จาก clinical มักไม่แตกต่างกัน )
1. Radiolucent lesions
2. Radiopaque lesions
3. Mixed radiopaque/radiolucent
I. Radiolucent lesion
of the jaws
A.
B. Lesions in the midline of the
maxilla
1. Median palatine cyst
2. Nasopalatine duct cyst (incisive
canal)
Lesions at the apex of the tooth
1. Dental granuloma
2. Periapical cyst (inflammatory)
C. Lesion around the crown of an
3. Residual cyst
impacted tooth
4. Periapical (dental) abscess
5. Cementoma (first stage)
1. Follicular cyst
6. Odontogenic keratocyst
2. Ameloblastoma
3. Ameloblastic fibroma
4. Odontogenic adenomatoid tumor
5. Odontogenic myxoma
6. Odontogenic keratocyst
E
.
D. Soap-bubble-like
radiolucencies
1. Multilocular cyst
2. Aneurysmal bone cyst
3. Ameloblastoma
4. Odontogenic myxoma
5. Central giant-cell
granuloma
6. Odontogenic keratocyst
E. Lesions that destroy the cortical
plate
1. Metastatic tumor
2. Primary malignant tumor
3. Osteomyelitis
F. Miscellaneous radiolucent
lesions
1. Lateral periodontal cyst
2. Idiopathic bone marrow cavity
3. Hematopoietic marrow
4. Gingival cyst
5. Hemangioma (central)
6. Osteoporosis
7. Stafne's bone cavity
II. Radiopaque lesions of the jaws
1. Cementoma (third stage)
2. Compound or complex odontoma
3. Ossifying fibroma
4. Osteoma
5. Torus
6. Root fragment or foreign body
7. Focal sclerosing osteomyelitis
8. Osteogenic sarcoma
9. Chondrosarcoma
10. Metastatic tumor
11. Paget's disease
III. Mixed radiolucent/radiopaque lesions of the jaws
1. Cementoma (second stage)
2. Cystic odontoma
3. Ossifying fibroma
4. Adenomatoid odontogenic tumor
5. Calcifying epithelial odontogenic tumor (Pindborg)
6. Calcifying odontogenic cyst (Gorlin)
7. Ameloblastic fibroodontoma
8. Ameloblastic odontoma
9. Osteogenic sarcoma
10. Chondrosarcoma
Aspiration Biopsy
• straw-colored fluid : most likely to be a cystic lesion
• pus : an inflammatory or infectious process
• White keratin-containing fluid : odontogenic keratocyst
• Air may indicate a traumatic bone cavity
• Blood represent several lesions : the most important is
vascular malformation
inability to aspirate (vacuum within the syringe) is
usually indicative of a solid process such as a
neoplasm.
Indications for excisional biopsy
•
small
•
radiographically benign lesions
•
accessible and can be removed
without encroachment on adjacent
structures.
Odontogenic cysts
• Inflammatory
Radicular (periapical) Cyst
Paradental Cyst
• Developmental
–
Dentigerous (follicular) Cyst
–
Developmental Lateral Periodontal Cyst
–
–
Odontogenic Keratocyst (OKC
Glandular Odontogenic Cyst (GOC
• True cyst :
epithelium lining a collagenous cyst wall
• Histologically
a fibrous connective tissue
stroma with multiple
cavernous and sinusoidal
spaces with multinucleated
giant cells within the
stroma
Enucleation is the treatment of choice
CLASSIFICATION OF JAW CYSTS
A. Developmental
1.
Odontongenic
a. Follicular cyst
b. Odontogenic keratocyst
c. Eruption cyst
d. Alveolar cyst of infants
e. Gingival cyst of adults
f. Developmental lateral periodontal cyst
2.
Nonodontogenic
a. Nasopalatine duct cust
b. Midpalatal cyst of infants
c. Nasolabial cyst
d. Globulomaxillary cyst, median mandibular cyst, and median alveolar cyst *
B. Inflammatory
a. Radicular cyst
1. Periapical cyst
2. Inflammatory lateral periodontal cyst
C. Nonepithelial
a. Idiopathic bone cavity (traumatic, solitary, hemorrhagic
bone cyst)
b. Aneurysmal bone cyst
c. Stafne's mandibular lingual cortical defect
CLASSIFICATION OF ODONTOGENIC TUMORS
A. Benign epithelial odontogenic tumors
1. Tumors producing minimal inductive change in the connective
tissue
a. Ameloblastoma
b. Calcifying epithelial odontogenic tumor (Pindborg tumor)
c. Odontogenic adenomatoid tumor (adenoameloblastoma,
adenomatoidodontogenic tumor)
d. Calcifying odontogenic cyst (Gorlin's cyst)
2. Tumors producing extensive inductive change in the connective
tissue
a. Ameloblastic fibroma
b. Ameloblastic fibroodontoma
c. Ameloblastic odontoma (odontoameloblastoma)
d. Odontoma
1. Compound-composite odontoma
2. Complex odontoma
B. Mesenchymal odontogenic tumors
1. Odontogenic fibroma
2. Odontogenic myxoma
3. Cementoma
a. Periapical cemental dysplasia
b. Cementifying fibroma
c. Benign cementoblastoma
4.
Dentinoma
C. Tumors of unknown origin
1.
Melanotic neuroectodermal tumor of infancy
D. Malignant odontogenic tumors
1.
2.
3.
4.
Primary intraosseous carcinoma
Ameloblastic fibrosarcoma
Ameloblastic dentinosarcoma
Ameloblastic odontosarcoma
Dentigerous (follicular) Cyst
Definition: assosiated with crown of unerupted tooth
• accumulation of fluid between reduced enamel epithelium and a
completed tooth crown
• most common developmental cyst (24%)
Dentigerous (follicular) Cyst
• Teenage, early childhood
• mandibular 3rd molars, maxillary canines, and maxillary third molars
• asymptomatic , impacted tooth , bony expansion
Treatment :
• enucleation
• decompression followed by enucleation if large.
Radiographic Features
• Unilocular radiolucency
• well defined sclerotic margins encircling the
crown of an unerrupted tooth
• Mandibular cyst can displace into ramus/inferior
border of mandible
• Maxillary cyst can displace tooth into maxillary sinus
Radiographic Features
• Histologically:
a cyst composed of thin
connective tissue walls
lined by stratified nonkeratinizing squamous
epithelium over a
fibrocollagenous cyst wall
Neoplastic potential
• Turn to true neoplasm
– SCCA
– Mucoepidermoid CA
• 17% of Ameloblastoma from dentigerous
cyst
Odontogenic keratocyst (OKC)
Parakeratinizing Odontogenic Keratocyst
Keratocystic Odontogenic Tumor (WHO)
• WHO  classify as tumor
– Soft tissue extension, extension to adjacent bone,
bony destruction
• Thought to develop from remnants of dental
lamina(rests of Seres) , may no tooth associated
Odontogenic keratocyst (OKC)
Clinical :
• any age, peak incidence 2nd- 3rd decades
• 75% at mandible
– mostly 3rd molar and ramus
• Symptomatic  Swelling, pain, trismus, sensory
deficit, infection (most common)
Odontogenic keratocyst (OKC)
• Diagnosis : histologic
• High recurrence rate :
– Only enucleation : 62.5%
– Enucleation + careful curettage: < 10%
Why high recurrence ?
1.
2.
3.
4.
5.
**Daughter/ Satellate cyst formation**
Collagenase activity of the cyst
Remnant of dental lamina rest at the cyst wall
PG- induced bone resorption
Increase mitotic activity
** OKC need aggressive treatment **
Radiographic
Features
unilocular/ multilocular
radiolucency
well circumscribed with
sclerotic border
teeth may displaced
may seen cortical
perforation
Radiographic Features
• CT scan
– Assess large lesion
– Assess maxillary lesion
• Gorlin syndrome  metachronous,
synchronous cyst
Histologic : specific criteria
1. Thin,stratified squamous epithelium
2. Prominent columnar or cuboidal
basal cell layer with dense nuclear
staining with palisading
“tombstone appearance”
3.
4.
Corrugated surface
Parakeratinizing stratified squamous
epithelium
Not pathognomonic
Luminal material : straw-colored clear to
creamy white keratin –filled material
Treatment
• Careful enucleation + partial bone removal
• Curretage
• Peripheral ostectomy with rotary blur
• Excision
– Bone penetration  remove periosteum
• Remove cyst lining, satellite cyst, dental
lamina rest
Treatment
– Recurrent: within 5 years
– Close radiographic F/U
• Early detection
• Decrease complication of recurrent
• > 1 cyst  Family history (Gorlin
syndrome)
• Carnoy’s solution
– Controversial
– Chemical cauterization
Basal cell nevus syndrome
(Gorlin syndrome)
•Autosomal dominant
•Large variation in expression
•Mutation of PTCH tumor supp
gene
•Multiple OKC of jaw
multiple basal cell CA
Frontal bossing, mandibular
prognathism
Palmar,plantar pitting, bifid ribs
Calcification of falx cerebri
Basal cell nevus syndrome
(Gorlin syndrome)
• Recurrence  new occurrence
• Large lesion  decompression
• Teeth should be saved
– Canine, incisor, 1st molar
Radicular cyst
• Periapical cyst, periradicular
cyst
Clinical
Asymptomatic
• the most common
odontogenic cyst (65%)
• Arise from the epithelial cell
rests of Malassez in
response to inflammation
Associated with Nonvital
tooth
Radiographic findings
Microscopically
cyst with a connective
a pulpless, nonvital tooth
that has a small welldefined periapical
radiolucency at its apex
tissue wall that may vary in
thickness, a stratified
squamous epithelium lining,
and foci of chronic
inflammatory cells within the
lumen
Treatment is extraction of the affected
tooth and its periapical soft tissue or
root canal if the tooth can be preserved.
(1,2)Periapical cyst in 60-year-old woman. CT scan demonstrate
radiolucent lesion (arrows) surrounding the apex of molar. defect with
denfilling (arrowhead) is present within the crown of the tooth.
(3) Periapical cyst in 40-year-old man. Panorex imdemonstrates circular radiolucent lesion (arrow) at the apex of molar.
Note the dental filling (arrowhead)
Odontogenic tumor
Ameloblastoma
• Unicystic
• Interosseous
• Peripheral
Ameloblastoma
Interosseous type
• Solid, not peripheral
• Arised from lining odontogenic cyst,
reduced enamel epithelium, odotogenic
rest
Ameloblastoma
Interosseous type
• 80% mandible
• Maxilla  may involve sinonasal region
• Location of tumor are important for long
term prognosis
– Anterior maxilla/ body of mandible   
– Posterior ramus of mandible   
Ameloblastoma
Interosseous type
Radiographic findings
• Small unilocular radiolucency, well dermacrate
• Large  “Soap bubble”, honeycomb
appearance
– May resorp root in long-standing lesion
• Desmoplastic type
– Mixed radiolucent radiopaque lesion
– Maxilla and anterior portion of jaws
Histopathology : 6 patterns
1. Follicular
2. Plexiform
The two most frequent patterns are the
follicular and plexiform
3. Basal cell
4. Acanthomatous
5. Granular cell
6. Desmoplastic
Histologic subtypes are not of therapeutic and
prognosis important
Vickers & Gorlin criteria
•
•
•
•
Columinar basilar cells
Palisading of basillar cells
Polarization of basillar cells
Hyperchromatism of basal cell nuclei in
the epithelial lining
• Subnuclear vacuolization of cytoplsam in
basillar cells
(c) High-power photomicrograph
hematoxylin-eosin [H-E] stain) reveals
numerous well-defined islands of
odontogenic epithelium with palisading
and polarizing nuclei (arrows)
Natural history
• Ability to infiltrate medullary bone and
relative inability to infiltrate compact bone
– Dense compact bone
• Inferior border of mandible, ramus
– Outer periosteum is barrier
• The location of tumor
– Posterior maxilla, involve orbit
Treatment
• High recurrance
– Tumor infiltrate trabeculae of cancellous bone
Mandibular ameloblastoma
• 1cm of medullary margin
– Proximal &distal
– Lingual & buccal cortical bone sacrificed
• Not include soft tissue outside periosteum
Ameloblastoma
Interosseous type
Maxillary Ameloblastoma
• Margin is more important
– Fossen section for soft tissue margin
– Margin 1-2 cm
• Spare vision, vital structure
• F/U  extremely important
Ameloblastoma
Unicystic type
• Unicystic
– Intraluminal
– Mural
– Intramural
Ameloblastoma
Unicystic type
Definition
• Unilocular
• Unicystic
• Patho lining of ameloblastoma
– Vickers & Gorlin criteria
• * not invade connective tissue *
Therapeutic planning & clinical behaviors
Ameloblastoma
Unicystic type
• 15% of Ameloblastoma
• Posterior mandible
• Asymtomatic
• Radiographic feature
– Radiolucent, unilocular
– Well dermacrate
Treatment
• Enucleation
– Histo  Vickers & Gorlin criteria for Dx
Ameloblastoma
• Histo: characteristic of luminal or intaluminal
involvement
– Radiograph singular unilocular radiolucency
• No septate
– Intra-op confirm of unilocular
– No multilocular, multicystic, cortical
perforation, soft tissue involvement
– Size < 2 cm
Peripheral Ameloblastoma
• Mucosal mass from gingiva/ alveolar
mucosa
• From dental lamina rests/ basal cells of
mucosa
• ** Not infiltrate underlying bone**
• Bone involvement  intaosseous ameloblastoma
Peripheral Ameloblastoma
Diagnosis
• CT / MRI
• Excision, patho comfirm margin
Malignant ameloblastoma
• Classic benign histopatho feature
• Metastasis to distant location
– Lung ( most common)
– Cervical LN
• Treatment
Depend on degree and site of involvement
– Excision
– RT (option)
Radiographics
a unilocular or multilocular radiolucency
with ill-defined borders,
(making it difficult to determine the exact
size of the lesion)
Buccal and lingual cortical expansion is
common, even progressing to cortical
perforation
Root resorption occurs infrequently.
Histopathology
• The ameloblastoma is unencapsulated,
so it typically exhibits
“ an infiltrative growth pattern into surrounding tissues ”
The basal cells in the epithelium are columnar and
hyperchromatic and demonstrate reverse polarity,
( in which the nuclei move from the basement membrane pole of the cell
to the opposite pole)
• The two most frequent patterns are the follicular and plexiform
Odontoma
most common
odontogenic tumor of the mandible
approximately 67% of all cases
consists of various tooth components,
including dentin and enamel
50% associated with an impacted tooth
Forming between the roots of
teeth, the tumor
is initially radiolucent but
evolves to contain small
calcifications.orms radioopaque
mass with alucent rim
Malignant Odontogenic Tumors
• Primary Intraosseous Carcinoma
• extremely rare tumor
• may be of three different types :
1.
Arising from an odontogenic cyst
2.
Developing from an ameloblastoma
Well differentiated (malignant ameloblastoma)
Poorly differentiated (ameloblastic carcinoma)
3.
Arising from odontogenic epithelium
SURGICAL MANAGEMENT OF ODONTOGENIC CYSTS
AND TUMORS
goals of management of benign odontogenic cysts
and tumors :
(1) remove all abnormal tissue
(2) conserve healthy bone and dental structures
(3) preserve adjacent structures such as the inferior alveolar
nerve
(4) restore the surgical defect to its presurgical state of
anatomic form and function
(5) prevent recurrence of the lesion.
•
Enucleation of a lesion
: involves local removal of the lesion by instrumentation
in direct contact with the lesion
•
Resection
: involves incision or osteotomy through uninvolved
tissue adjacent to the lesion without disruption
of the lesion
•
Composite resection
: involves removal of tumor, adjacent bone, soft tissue,
and contiguous lymph node channels
• Enucleation and curettage
–
Odontogenic cysts:
Virtually all unless recurrent
– Odontogenic tumors:
Odontoma
Ameloblastic fibroma
Ameloblastic fibroodontoma
Adenomatoid odontogenic tumor
Calcifying odontogenic cyst
Cementoblastoma
Central cementifying fibroma
Unicystic ameloblastoma (except mural type)
• Marginal or partial resection
– Odontogenic cysts:
Recurrent odontogenic keratocyst
– Odontogenic tumors:
Ameloblastoma (solid and mural type unicystic)
Calcifying epithelial odontogenic tumor (Pindborg tumor)
Odontogenic myxoma
Ameloblastic odontoma
Squamous odontogenic tumor
• Composite resection *
– Odontogenic tumors:
Malignant ameloblastoma
Ameloblastic fibrosarcoma
Ameloblastic odontosarcoma
Primary intraosseous carcinoma
These lesions are malignancies and may be treated variably and
with additional modalities such as radiation or
chemotherapy.
management of
odontogenic lesion of
mandible