History :
•CUZACK (1827)-First Recognized
•FALKSON (1879)–Description
•MALASSEZ (1885)–Admantinoma
•IVY &CHURCHILL (1934)–Ameloblastoma
•Unicystic ameloblastoma –Robinson and
Martinez in 1977
ORIGIN
•Cell rests of enamel organ
–Dental lamina remnants
–Hertwig’s sheath
–Rests of malassez
•Epithelium of Odontogenic cysts (Dentigerous cyst &
Odontomas)
•Disturbances in developing enamel organ.
•Heterotropic epithelium in other parts of the body,
especially the Pituitary Gland.
•Basal cells of oral epithelium.
extra osseous
•Dental lamina
ameloblast
•Oral epithelium
Incidence
1% of oral tumors
18-20% of odontogenic
tumors
Clinical features
20-50 years
Number of cases reported in
children
Youngest reported one month old
Oldest 98 yrs
Secondary infection
Ulceration
Egg shell crackling
Extra osseous Small nodule
Classification
Robinson and Martinez 1977
Anatomic site
1.Central /intraosseous
i.Multicystic/Conventional
ii.Unicystic
iii.solid
2.Peripheral/ extra osseous
Radiological features
•Numerous well defined radioluscency of varying
diameter
•Honey comb
•Soap bubbleappearance
•Unicystic radiolucent lesion indistinguishable
with cysts
Ameloblastoma
With in medullary cavity
Scalloping of inner cortex
Pressure erosion
Shell remains
C T SCAN
When maxillary sinus involved
Cloudiness of sinus
Destruction of wall
Unicystic in maxilla
Histopathology
•Follicular
•Plexiform
•Acanthomatous
•Granular cell
•Desmoplastic
•Basal cell type
Follicular
Plexiform
Acanthomatous
Granular cell
Desmoplastic
Basal cell
Unicystic ameloblastoma
Ackerman in 1988
1.Type-I Luminal(consisted of unilocular cystic lesions lined by
epithelium exhibiting features of ameloblastoma).
1.Type-II Intra luminal(showed epithelial nodules arising from
the cystic lining and projecting into the cyst lumen. These
nodules comprised epithelium with a plexiform or follicular
pattern resembling that seen in intraosseous ameloblastoma.).
1.Type-III Mural ameloblastoma(characterized by the presence of
invasive islands of ameloblastomatous epithelium in the
connective tissue wall of the cyst, and these islands may or may
not be connected to the cyst lining)
Mural Ameloblastoma
Peripheral ameloblastoma
•Peripheral ameloblastoma (PA) is a rare odontogenic tumor that
accounts for 1% for all ameloblastomas.
•Kurifirst reported PA in 1911
•In 1959, Stanley and Kroghdefined the clinical and histopathologic
characteristics.
•The strict definition of PA according to Buchner and Scuibba(1987)
excludes lesions in extragingival locations.
The etiology of PA is unclear. The tumor can derive from the extraosseous
epithelial remnants of the dental lamina or from the basal cell layer of the
oral mucosa, which is believed to have odontogenic potential
•The differential diagnosis usually includes
–Pyogenic granuloma, peripheral
–Giant cell granuloma,
–Peripheral odontogenic fibroma,
–Peripheral ossifying fibroma,
–Papilloma,
–Epulis.
•Only four cases of malignant PA have been
reported to date.
Treatment
–Behavior and potential of tumor
–Growth characteristics
–Anatomic site
–Clinical extent
–Size of tumor
–Histologic pattern
Less than complete
excision is equivalent to
planned recurrence
General principles
1.Definitive & offer best cure
2.Curettage and enucleation –recurrence
3.Curettage condemned
4.Cancellous bone –readily infiltrated
resorbed by tumor
5.Dense cortical bone -temporary barriers
A safe margin of uninvolved bone is 2 cm for
solid and multicystic lesion
1-1.5 for unicystic and peripheral lesions
Resorption of cortical bone –periosteum
involved –surrounding soft tissue and muscle
Post treatment follow up 15-20 yrs
Specific principles
Intra osseous solid / multi cystic
ameloblastoma
Excision of lesion
Enbloc resection --without continuity
defect
Enbloc resection–with continuity
defect
Inferior alveolar nerve if in lesion-sacrificed
Nerve grafting best to perform at time of
resection
Resection should be exterior to tumor
involving plane
A thin inferior border preserved may fracture-
reconstruction plate
<1 cm not practical
Resection with sharp cutting instrument
Grinding with bur –not allow histologic
evaluation at tumor bone interface
Confirmed by frozen section
Immediate reconstruction
Delayed reconstruction
•Autogenous free bone graft
•Allogenic bone with reconstruction plate
•Platelet rich plasma mixed into a cortical/
cancellous bone graft
•If sufficient soft tissue not available -
vascularized composite pedicle graft
•Delayed reconstruction : reconstruction plate to
maintain resection space
An anatomic classification of maxillary ameloblastoma as
an aid to surgical treatment
I T Jackson and P P Callan
J Cranio Maxillofac Surg 1996;24; 230
Group Itumors confined to maxilla with out involving orbital floor
-Partial maxillectomy
Group IItumor involving orbital floor not the periorbital tissue
-total maxillectomy
Group IIItumor involving orbital contents
-total maxillectomy with orbital excentration
Group IVtumor involving skull base
-total maxillectomy with orbital excentration and anterior
skull base resection
Unicystic ameloblastoma
Initial diagnosis
Dentigerous cyst or OKC
Enucleation or marsupialization?
Careful assessment
Biopsy may not confirm
Physical basis cleavage plane
Microscopic section R without CD or
R with CD
Peripheral ameloblastoma
Enmass excision
With overlying mucosa periosteum
alveolar bone and adjacent teeth
1-1.5 resection margin
Carnoy’ solution
•Culter & Zollinger1933 described as a
sclerozing agent for the treatment of cysts and
fistulae, and remains in use today as a fixative
Composition
i.Glacial acetic acid
ii.Absolute alcohol
iii.Chloroform
iv.Ferric chloride
•Depth of penetration 1.5-1.8 mm
Unicystic ameloblastoma –use of Carnoy’s
solution after enucleation
P K Lee N Samman
Int J Oral Maxillofac Surg 2004; 33 ; 263-7
Cryotherapy
Adjunct to curettage
Devitalize the tissue with liquid nitrogen
Depth 1.5 cm
Jaw can be frozen the entire thickness
Complication sequestration and pathologic
fracture
Transient anesthesia
Management of mandibular ameloblastoma
treatment algorithm
Daniel E Sampson, M. Anthony Pogrel
J Oral Maxfac Surg 57; 1074-77 :1999
•Curettage recurrence
•Curettage with cryotherapy
•Confined to bone respond well to cryotherapy
•Soft tissue extension –necrosis
•Pathologic fracture –secondary to necrosis and
demineralization of bone
•Immediate bone grafting
Radiotherapy
Inoperable cases
Invasion into cranium
Primarily intraosseous-resistant
Extra osseous ameloblastoma -reduced
Possible osteoradionecrosis
Cause of metastasis
MALIGNANT BEHAVIOUR AND META STASIS
•Malignant ameloblastomais a histologically well-
differentiated, benign appearing ameloblastoma with
metastatic disease histologically identical to the primary
tumor.
•Ameloblastic carcinomais an ameloblastoma with
histological malignant transformation in the primary
lesion with or without metastatic disease.
•Metastases from malignant ameloblastomas have been
reported in the
–lung (75%),
–cervical lymph nodes (15%),
–spine (15%), and,
–less frequently, in the liver, skull, diaphragm, and brain.
•Markedly aggressive clinical course
•Quiescent chronicity
•After irradiation
Pulmonary metastasis of ameloblastoma
James M Henderson, J R Sonnet
J. Oral Surg Oral Path Oral Med Oral Radiol Endod;88 ;170-6:1999
•41 cases metastatic to lung has been reported
•Inadequate and inappropriate treatment –recurrence
increased risk of metastasis
•Route aspiration of tumor particles/ hematogenous
spread
Rational approach to diagnosis and treatment of
ameloblastoma and OKC
Karen A O M Chapelle, Paul J W Stoclinge
British J Oral Maxfac Surg 42; 381-390 :2004
ameloblastoma
Ameloblastoma in children
R A Ord, R H Blanchaert Et Al
J Oral Maxfac Surg 60; 762-70 : 2002
Differ
Higher % unicystic and fast growing
Mural invasion
More aggressive surgery necessary
In discussion
Arie Shteyer suggest
1.Precise differential diagnosis
2.Conservative approach
Decompression-Iodoform gauze
soaked in whiteheads varnish
3.Long term follow up
4.recurrence extensive surgery
Conclusion
•Careful examination
•Appropriate treatment
•Complete cure
•Reconstruction
•Follow up