Odontogenic tumor

Ameloblastoma. A, Gross photograph of a mandibular resection specimen. B, The radiograph of the specimen shows a large radiolucent defect associated with an inferiorly displaced third molar.

Ameloblastomalarge expansile mass of the anterior mandible

Ameloblastoma: Destructive radiolucent lesion associated with root resorption of the anterior teeth.

Ameloblastoma (follicular pattern). Multiple islands of odontogenic epithelium demonstrating peripheral columnar differentiation with reverse polarization. The central zones resemble stellate reticulum and exhibit foci of cystic degeneration.

Ameloblastoma (follicular pattern) . This high power photomicrograph highlights the peripheral columnar cells exhibiting reverse polarization.

Ameloblastoma (plexiform pattern) . large anastomosing cords of odontogenic epithelium. The high-power view(inset) reveals columnar cells

with reverse polarization.

• Ameloblastom a (acanthomatous pattern) Islands of ameloblastoma demonstrating central squamous differentiation.

Ameloblastoma (granular cell variant). Tumor islands exhibiting cells with prominent granular cytoplasm.

Ameloblastoma (desmoplastic variant). Thin cords of ameloblastic epithelium within a dense fibrous connective tissue stroma.

Ameloblastoma (basal cell variant ). Island of hyperchromatic basaloid cells.

Unicystic ameloblastoma. A large radiolucency in a 7-year-old boy with displacement of the developing second molar to the inferior border of the mandible. This was believed to be a large dentigerous cyst.

Unicystic ameloblastoma (luminal type). The cyst is lined by ameloblastic epithelium showing a hyperchromatic polarized basal layer. The overlying epithelial cells are loosely cohesive and resemble stellate reticulum.

Unicystic ameloblastoma (intraluminal plexiform type). Photomicrograph of the intraluminal mass arising from the cyst wall in the same patient shown in The inset shows the intraluminal mass at higher magnification.

Unicystic ameloblastoma (mural type). Islands of follicular ameloblastoma are infiltrating into the fibrous connective tissue wall.

Adenomatoid odontogenic tumor. A well circumscribed solid mass can be seen enveloping the crown of this tooth.

Adenomatoid odontogenic tumor (follicular type) . Radiolucent lesion involving an unerupted mandibular first premolar. Fine snowflake calcifications are present in the

radiolucent area. In contrast to the usual dentigerous cyst. the radiclucencyextends almost to the apex of the tooth.

Adenomatoid odontogenic tumor. Low-power view demonstrating a thick capsule surrounding the tumor.

Adenomatoid odontogenic tumor. Higher magnification showing the duct like epithelial structures. The nuclei of the columnar calls are polarized

away from the central spaces.

Calcifying epithelial odontogenic tumor. Honeycombed multilocular radiolucency containing fine calcifications.

Calcifying epithelial odontogenic tumor. Sheets of polyhedral tumor cells with prominent eosinophilic cytoplasm and intercellular bridging. Pools of amorphous eosinophilic amyloid are present. Multiple lesegang ring

calcifications are seen in the inset

Squamous odontogenic tumor. Lucent defect extending along the roots of the lateral incisor and first premolar teeth.

Squamous odontogenic tumor. Islands of bland appearing squamous epithelium in a fibrous stroma. Microcyst formation is seen. The inset shows one of the tumor

islands at higher power.

Ameloblastic fibroma. Well-defined radiolucent defect associated with an unerupted second molar.

Ameloblastic fibra-odontoma. Radiolucent defect in the ramus containing small calcificat ions having the radiodensity of tooth structure.

Ameloblastic fibroma. long, narrow cords of odontogenic epithelium in a richly cellular, primitive mesenchymal stroma. Note

the peripheral columnar differentiation (inset).

Ameloblastic fibre-odontoma. The soft tissue component of the tumor is indistinguishable from an ameloblastic fibroma. Developing rudimentary tooth like

structures are shown (inset).

Ameloblastic fibrosarcoma. The cellular mesenchymal tissue shows hyperchromatism and atypical cells.A small island of ameloblastic epithelium is present.

Compound odontoma Surgical specimen consisting of more than 20 malformed tooth like structures.

Compound odontoma. Multiple tooth lets preventing the eruption of the mandibular cuspid.

Complex odontoma. This decalcified section shows a disorganized mass of dentin intermixed with small pools of enamel matrix.

Odontogenic fibroma. Apical radiolucent lesion in the incisor and premolar area.

Odontogenic fibroma (simple type). Scattered fibroblasts within a collagenous background. No epithelial rests were found on multiple sections from this tumor.

Odontogenic fibroma (World Health Organization [WHO] type. A cellular fibroblastic lesion containing narrow cords of odontogenic epithelium.

Granular cell odontogenic tumor. Radiolucent lesion involving the apical area of endodontically treated maxillary teeth.

Granular cell odontogenic tumor. Sheet of large granular mesenchymal cells with small nest s of odontogenic epithelium.

Odontogenic myxoma of the right mandible.

Odontogenic myxoma showing characteristic multilocularity .

Odontogenic myxoma exhibiting typical bland myxoid appearance .

Odontogenic fibromyxoma with collagen bundles and residual bony trabecula (center) evident .

Ameloblastic carcinoma. A, Rapidly growing tumor showing prominent labialexpansion of the mandible in the incisor and premolar area. B, The panoramic

radiograph shows irregular destruction of the mandible.

Ameloblastic carcinoma. Ameloblastlc epithelium demonstrating hyperchromatism. pleomorphism, and numerousmitotic figures.

Clear cell odontogenic carcinoma. Tumor island demonstrating cells with a clear cytoplasm. Note the peripheral columnar differentiation.