Mandible and maxilla

Last revised 8 February 2007

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Table of contents

Primary references, normal anatomy, normal anatomy/histology-teeth

Temporomandibular joint: hypoplasia, hyperplasia, pain-dysfunction syndrome

Inflammatory: general, central giant cell granuloma, dental granuloma, hyaline ring like structures, osteomyelitis, periodontitis, peripheral giant cell granuloma

Odontogenic cysts: general, calcifying odontogenic cyst, dentigerous, eruption, gingival, glandular, keratocyst, lateral periodontal, nevoid basal cell carcinoma syndrome, paradental, periapical (radicular), residual

Fissural and other non-odontogenic cysts: general, dermoid cyst, epidermoid cyst, globulomaxillary cyst, median palatine cyst, nasolabial cyst, nasopalatine cyst, palatine cyst

Benign tumors / tumorlike conditions: odontogenic tumors-general, WHO classification, adenomatoid odontogenic, ameloblastic fibroma, aneurysmal bone cyst, calcifying epithelial odontogenic tumor, cementifying fibroma, cementoblastoma, cementoma, cherubism, desmoplastic fibroma, fibrous dysplasia, florid cemento-osseous dysplasia, giant cell tumor, gigantiform cementoma, juvenile ossifying fibroma, Langerhans cell histiocytosis, latent bone cavity, melanotic neuroectodermal tumor of infancy, meningioma, myxoma, odontogenic fibroma, odontoma, ossifying fibroma, osteoblastoma, osteoma, Paget’s disease, periapical cemental dysplasia, simple bone cyst, squamous odontogenic tumor

Malignant tumors: ameloblastic carcinoma, ameloblastic fibrosarcoma, ameloblastoma, clear cell carcinoma of salivary gland, clear cell odontogenic carcinoma, lymphoma, malignant ameloblastoma, metastases to jaw, odontogenic carcinoma, odontogenic ghost cell tumor, osteosarcoma, primary intraosseous carcinoma

 

 

Primary references

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American Journal of Surgical Pathology (AJSP), March 1977 to Jan 2004

Archives of Pathology and Laboratory Medicine (Archives), January 1976 to March 2004

Human Pathology, March 1970 to Feb 2004

Modern Pathology, Jan 1988 to March 2004

Rosai, J:  Ackerman’s Surgical Pathology (8th Ed); Mosby-Year Book, Inc., 1996

Sternberg, S: Diagnostic Surgical Pathology (3rd Ed); Lippincott Williams & Wilkins, 1999

Journal search terms: jaw, mandible, maxilla, odontogenic, tooth, teeth

 

Please refer to these primary references for more detailed discussions and photographs

 

Normal anatomy

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Contain primitive embryonic structures from early fetal development to 25 years of age

Divided into alveolar bone (supports teeth) and body, with variable thickness ranging from paper thin overlying roots of cuspid (canines) and bicuspid (premolar) teeth to thick at apex of chin

Mandible: receptor for lower teeth; consists of curved horizontal body and two perpendicular rami

Maxillae: forms upper jaw, boundaries of roof of mouth, floor and lateral wall of nose, floor of orbit; consists of zygomatic, frontal, alveolar and palatine processes

Drawings: teeth and jaws

Mandible: outer surface, inner surface, lower dental arch

Maxilla: outer surface, nasal surface, opened from exterior, hard palate

Embryology: mandible of early fetus

 

Normal anatomy/histology-teeth

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Composed of outer enamel adjacent to dentin and inner pulp; surrounded by periodontal membrane and attached to bone by cementum

Development: (1) primitive oral cavity (dental lamina, derived from ectoderm) invaginates, acquires a bell shape, and ameloblasts develop along inner (concave) surface; called “enamel organ” at this stage; (2) dental papilla, derived from mesoderm, forms within “enamel organ”, is loose stellate reticulum; its outer layer matures to become odontoblasts; (3) dental sac or follicle forms from outer layer of dental papillae / odontoblasts, which form periodontium, a fibrous sheath enveloping the tooth; (4) inner layer of dental sac become cementoblasts and deposit cement over newly formed dentin, and outer layer of dental sac becomes osteoblasts and produces alveolar bone

Three phases of activity: (1) initiation of entire deciduous dentition (first set of teeth) during second month of gestation (above); (2) initiation of permanent dentition (second set of teeth) and extension of dental lamina distal to dental organ of second deciduous molar; (3) after 5-6 years of activity, dental lamina breaks up into epithelial rests or islands that may develop into odontogenic cysts or tumors

Teeth from medial to lateral: incisors, canines (cuspids), premolars (bicuspids), molars

 

Ameloblasts (adamantoblasts): secrete enamel matrix

Cementicles: rounded, strongly basophilic structures normally within periodontal ligament

Cementum: similar to bone, cellular or acellular, intensely basophilic; also present in other parts of skeletal system

Dental lamina: epithelium with potential to develop teeth; derived from primitive oral epithelium along free margin of arches of jaws

Dental pulp: hypocellular, myxoid; resembles myxoma but is compact and has peripheral odontoblasts

Dentin: radially striated due to numerous minute canals (dentinal tubules) containing cytoplasmic processes from odontoblasts; resembles osteoid if tubules / canals are absent

Enamel: thin rods or prisms separated on cross section by concentric lines of Retzius

Nests of Serres: nests of ameloblasts, cementoblasts and odontoblasts located in alveolar mucosa, due to breakup of dental lamina

Odontoblasts: form dentinal matrix

Rests of Malassez: nests of ameloblasts, cementoblasts and odontoblasts embedded within periodontium

Drawings: histology of growing tooth, permanent teeth, tooth, tooth in situ, tooth of early fetus

Images: developing tooth (odontoblast and periodontal membrane)

 

 

Temporomandibular joint

Hypoplasia

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Unilateral or bilateral involvement of mandibular condyle

Associated with facial asymmetry and abnormal function, anomalies of ear, temporal bone and macrostomia (exaggerated width of mouth)

May be due to mandibular fracture or trauma during growth

 

Hyperplasia

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Usually an isolated finding in adults with unilateral facial enlargement

Also associated with hemihypertrophy

May be related to synovial chondromatosis or osteochondromatosis

Gross: large condyle

Micro: thick and irregular hyaline or fibrohyaline cartilage on articular surface of condyle; may be markedly cellular

DD: chondrosarcoma (if cellular)

 

TMJ pain-dysfunction syndrome

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Symptoms: limitation of jaw movement, pain, discomfort, tenderness, joint clicking

Usually nonspecific pathologic features

 

 

Inflammatory lesions

General

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Usually due to untreated dental caries, causing inflammation of pulpal or soft tissue portions of teeth, then inflammation of cancellous bone and connective tissue surrounding dental root apices

 

Central giant cell granuloma

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Also called giant cell reparative granuloma

Central if intraosseous; peripheral if extraosseous

May be due to recurrent slow, minute hemorrhages; often associated with trauma

Children and young adults, usually females

Lesion appears to be unique to jaw; usually anterior mandible

Xray: radiolucent, multilocular lesion, may have resorption / movement of teeth and penetration of jaw cortex

Treatment: excision, thorough curettage

May recur

Gross: cystic bone lesion

Micro: numerous osteoclast-like giant cells near hemorrhagic areas, cellular vascular and fibrous stroma, new bone formation at edge of lesion; frequent mitotic figures; no necrosis

Micro images: osteoclast-like giant cells in cellular stroma #1, #2, #3

Micro images (Mod Path subscribers): low power, osteoclast-like giant cells

Positive stains: CD68 (giant cells)

EM: fibroblasts, myofibroblasts, histiocytes

DD: giant cell tumor, hyperparathyroidism, aneurysmal bone cyst

 

Dental granuloma

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Also called localized osteitis

May undergo cystic degeneration forming radicular cyst (periapical cyst) [below]

Often found on dental Xrays

Gross: 1.5 cm or less

Micro: histiocytes and other chronic inflammatory cells surrounded by dense fibrous tissue

 

Hyaline ring-like structures

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Also called pulse granuloma (pulse is edible seed of legumes)

Associated with chronic periostitis

May be a degenerative change in vessel walls from vasculitis or a reaction to legume parenchymatous cells at various stages of digestion Micro: hyaline ring like structures, some containing granular necrotic material, surround giant cells, vessels and collagen, and are themselves surrounded by chronic inflammatory cells

 

Osteomyelitis

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Usually an extension of dental or periodontal infection

Late finding is atrophy of covering mucosa, dull and devitalized exposed bone

Usually due to Staphylococcus aureus; occasionally anaerobes

Xray: irregular, ill-defined, radiolucent lesions; may be subtle

Gross: sequestrum (dead bone)

Micro: abscess cavities, resorptive scalloping of margins of dead bone within large portion of maxilla or mandible

 

Chronic osteomyelitis

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Usually low grade, asymptomatic

Micro: marked new bone formation (irregular size and shape) with osteoblasts and osteoclasts mixed with mature lamellar bone, often scant inflammatory cells

DD: fibro-osseous lesions (ossifying fibroma, fibrous dysplasia)

 

Periodontitis

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Recurrent and continuous gingivitis that affects alveolar bone

Causes bone destruction and pockets around teeth > 3 mm in depth

Plaque within pockets serves as nidus for mineralization (dental calculus), causing progressive disease until gingival scarring and bony erosion lead to loss of teeth

Treatment: scaling and cleaning of root surfaces to remove focal irritants, surgery, brushing and flossing

 

Peripheral giant cell granuloma

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Also called giant cell epulis

Resembles pyogenic granuloma, but may erode alveolar bone or involve periodontal membrane

Usually women, mean age 30 years, although may involve children or elderly patients without teeth

May be due to trauma, local irritation or chronic infection

Recurs if not completely excised

Treatment: excision with curettage of base of lesion extending into adjacent periodontal membrane

Gross: inflammatory lesion up to 1.5 cm that protrudes from gingiva at site of chronic inflammation; covered by gingival mucosa or ulcerated

Micro: nonencapsulated aggregates of foreign body giant cells and fibroangiomatous stroma with hemorrhage, hemosiderin, acute and chronic inflammatory cells; alveolar bone often expanded in edentulous patients leading to superficial bone loss with peripheral cuffing

DD: giant cell granulomas of maxilla/mandible, giant cell “brown tumors” of hyperparathyroidism

 

 

Odontogenic cysts

Odontogenic cysts-general

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Derived from odontogenic epithelium (ameloblasts, cementoblasts, odontoblasts) around impacted or nonerupted teeth, or from epithelial rests or remnants of dental lamina

Rarely associated with carcinoma, usually squamous cell carcinoma; also mucoepidermoid carcinoma

References: Mod Path 2002;15:331

 

Calcifying odontogenic cyst

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Also called Gorlin cyst

A developmental cyst that presents as painless enlargement of maxilla or mandible, usually in canine-premolar region

Mean age 31 years, range 12-72 years, female predominance in some studies

Most appear to be non-neoplastic

May be associated with odontoma and ameloblastic fibrodontoma

Proposed classification differentiates this developmental cyst from a benign neoplasm (odontogenic ghost cell tumor or other odontogenic tumors with calcifying odontogenic cyst features) and odontogenic carcinoma, AJSP 2003;27:372

Xray: unicystic radiolucency with focal opacification

Treatment: complete excision conserving dental structures; usually does not recur

Gross: unicystic, often 2 cm or less; no solid areas

Micro: well defined layer of palisading basal cells, loosely arranged suprabasal epithelial cells resembling stellate reticulum; epithelium also contains pale, eosinophilic ghost cells that may keratinize or calcify; dentin may be laid down next to basal cells; variable foreign body reaction

Note: ghost cells also present in ameloblastoma and odontoma

Micro images (Mod Path subscribers): ghost cell keratinization, dystrophic calcification and palisading basal cells

DD: odontoma, cementoma, odontogenic keratocyst, craniopharyngioma, sweat gland tumor

 

Dentigerous cyst

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Surrounds crown of nonerupted permanent tooth in young adults

Common; found in 1% with complete dental Xrays

Due to fluid accumulating between ameloblasts (epithelium that produces the crown) and nonerupted tooth

Associated with missing tooth, usually permanent third molars and maxillary cuspids

May be destructive, causing bone expansion and teeth displacement

Don’t recur; recurrence suggests incomplete excision, keratocyst or other cystlike condition or ameloblastoma

Rarely transforms to ameloblastoma

Xray: unilocular radiolucency

Treatment: enucleation with tooth of origin

Micro: stratified squamous epithelium lining without keratinization continuous with ameloblasts of crown; also myxomatous fibrous tissue, dental organ epithelium; variable hyperplasia, calcification, metaplasia, dysplasia, neoplasia; no inflammation unless secondary infection

 

Eruption cyst

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Type of dentigerous cyst affecting erupting deciduous teeth

Children (11% during eruption of incisors and 30% of infants during eruption of deciduous cuspids and molars)

Treatment: removal of cyst overlying tooth

Gross: blue-red dome shaped lesion of alveolar ridge overlying erupting tooth

Micro: inflamed and hemorrhagic cyst wall lined by thin, nonkeratinizing stratified squamous epithelium

 

Gingival cyst

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Newborn infants, rarely adults

Also called Epstein’s pearls or Bohn’s nodules

Due to cystic degeneration of dental lamina

Usually disappear in weeks

Treatment: simple excision or wait

Gross: white nodules in gingiva

Micro: squamous or cuboidal lined inclusion cysts

 

Glandular odontogenic cyst

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Also called sialo-odontogenic cyst

Uncommon developmental cyst

More likely in men, mean age 50 years

Usually mandible

May recur after enucleation

Gross: multilocular

Micro: nonkeratinized stratified squamous epithelium mixed with cystlike spaces lined by cuboidal and ciliated epithelium, focal thickenings have mucous cells in pseudoglandular pattern

Micro images (Mod Path subscribers): focal thickenings with pseudoglandular formation

Positive stains: PAS+ diastase resistant pools in cystlike spaces

DD: mucoepidermoid carcinoma, adenomatoid odontogenic tumor, dentigerous cysts

 

Keratocyst

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10% of jaw cysts

Mean age 30-40 years

May be neoplastic due to frequent loss of heterozygosity of p16, p53, PTCH and MCC, Archives 2004;128:313

90% solitary; multiple tumors associated with nevoid basal cell carcinoma syndrome

May be destructive, 10-60% recur; more likely to recur if multiple, whether part of a syndrome or not

Sites: any position in jaw, may be superimposed over tooth root apices or adjacent to crowns of impacted teeth

Xray: multilocular or unilocular radiolucency in posterior mandible or maxilla; less often in anterior maxilla

Xray image (Mod Path subscribers): large mandibular lesion

Treatment: complete excision

May recur, invade bone or undergo malignant transformation into squamous cell carcinoma

Gross: contains cheesy keratinized debris, wrinkly white inner cyst lining

Micro: mildly verrucous, 6-10 cell thick, keratinizing, stratified squamous epithelium; prominent palisading basal cell layer, fibrous connective wall often is separated from epithelium; also daughter cysts with undulating tortuous projections of cyst; cyst may become secondarily inflamed

Orthokeratinized variant: orthokeratosis (anuclear keratin), granular layer and poorly organized basal layer; not syndrome associated, less aggressive behavior

Micro images: classic features, budding, daughter cyst1-multiple mandibular cysts, 2-low power, 3-calcification of falx cerebri (arrow), 4-plamar pit 

Micro images (Mod Path subscribers): parakeratinized epithelium with basal cell palisading, orthokeratinized variant with granular cell layer

 

Lateral periodontal cyst

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Rare developmental odontogenic cyst of alveolar bone at roots of mandibular cuspids or bicuspids

May be due to cystic degeneration of local epithelial rests

Treatment: surgical excision

Micro: very thin epithelium (1-2 layers)

 

Nevoid basal cell carcinoma syndrome

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Also called Gorlin-Goltz syndrome, basal cell nevus syndrome

Autosomal dominant, usually high penetrance but variable expressivity, incidence 1 per 60,000 people

Features: multiple odontogenic keratocysts, multiple basal cell carcinomas early in life (in 90%), congenital skeletal anomalies (bifid rib), dyskeratotic pitting of hands and feet (palmoplantar pits in 50-75% of adults, usually develop in teenagers, pits due to diminished stratum corneum), ectopic calcifications of falx cerebri (80-90% vs. 3-6% of normals); also bilateral calcified ovarian fibromas and medulloblastoma

Due to mutations in PTCH (PATCHED) tumor suppressor gene at 9q22.3, which allows unregulated cell division (mutation also present in keratocysts)

Case report of 24 year old man with multiple odontogenic keratocysts and cutaneous lesions, Archives 2003;127:e165

 

Paradental cyst

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Usually men

Associated with crown of tooth

Develops on buccal distal or mesial (“toward middle of front of jaw along curve of dental arch”) aspect of partially erupted mandibular third molar

Does not displace teeth

Treatment: enucleation

Gross: 1-2 cm cyst, attached to cemento-enamel junction and coronal (towards crown) portion of root

Micro: inflammatory cyst, otherwise similar to periapical cyst

 

Periapical (radicular) cyst

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Most common odontogenic cyst

Due to severe pulpal inflammation or pulp death, secondary to trauma or dental caries

Usually ages 20-39 years

Cyst lining derived from epithelial rests of Malassez left after tooth development

Usually maxillary incisors and mandibular molars

Incidental finding

Xray: radiolucency with prominent radiopaque margin of focal sclerosing osteomyelitis or osteitis

Treatment: enucleation

Gross: 1 cm or less, round or flask-shaped; may be attached to apex of extracted tooth

Micro: lined by hyperplastic squamous epithelium with diffuse inflammatory cells, variable keratinization and ulceration; may have goblet cells or hyaline bodies (Rushton bodies)

Rushton bodies: may be product of cyst epithelium resembling dental cuticle

 

Residual cyst

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Periapical cyst after extraction of involved tooth

 

 

Fissural and other non odontogenic cysts

General

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Fissural cysts occur at junction of developing structures in head and neck

Due to enclavement of epithelial tissue (“trapped in other structures”) and delay in development of growth centers

Not odontogenic origin

Medial: median mandibular, median palatal, nasopalatine cysts

Lateral: globulomaxillary, nasolabial cysts

 

Dermoid cyst

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Micro: squamous lining with cutaneous adnexae

 

Epidermoid cyst

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Micro: squamous lining without cutaneous adnexae

 

Globulomaxillary cyst

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Disputed as a specific entity

Considered an obsolete concept by some (J Oral Path 1985;14:1, J Oral Path Med 1989;18:125) but not all (Oral Surg Oral Med Oral Path 1993;76:182)

Arise in same area as nasolabial cysts but in alveolar bone at union of globular process and maxillary process

Most (or all) are considered of odontogenic origin

Xray: pear shaped radiolucency between maxillary lateral incisor and cuspid; causes divergence of tooth roots

Treatment: enucleation

Micro: lined by stratified squamous or respiratory type epithelium

 

Median palatine cyst

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Posterior to nasopalatine duct cyst

Due to enclavement of epithelium during fusion of right and left maxillary palatine processes

May be intraosseous or within soft tissues of palatine papilla

Xray: well circumscribed, midline radiolucency, usually in molar region

Treatment: enucleation

Micro: lined by stratified squamous epithelium or respiratory mucosa

 

Nasolabial cyst

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Also called nasoalveolar cyst, Klestadt cyst

Associated with fusion of maxillary and globular processes, may develop from caudal end of nasolacrimal rod or duct

Arises in soft tissue of upper lip or lateral aspect of nose, may be bilateral

More common in blacks and women

Often becomes infected, obliterates nasolabial fold

Treatment: enucleation

Micro: lined by stratified squamous or respiratory epithelium

 

Nasopalatine cyst

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Due to enclavement of vestigial oronasal cysts

Usually ages 30-59 years

May develop entirely within bone, within incisive papilla of anterior palatal gingiva or within bone and soft tissue

Micro: lined by stratified squamous or respiratory epithelium; prominent neurovascular bundle within connective tissue wall; variable cartilage

 

Palatine cyst

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Called Epstein’s pearls (also gingival cysts)

At junction of hard and soft palate in newborns

Micro: squamous or cuboidal lined inclusion cysts

 

 

Benign tumors / tumorlike conditions

Odontogenic tumors-general

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Uncommon

Arise from odontogenic epithelium

 

WHO classification

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MALIGNANT TUMORS

 

1. Odontogenic carcinomas

 

- Metastasizing (malignant) ameloblastoma

- Ameloblastic carcinoma (primary and secondary type)

- Primary intraosseous squamous cell carcinoma (solid, derived from KCOT and derived from odontogenic cysts)

- Clear cell odontogenic carcinoma

- Ghost cell odontogenic carcinoma

 

2. Odontogenic sarcoma

 

- Ameloblastic fibrosarcoma

- Ameloblastic fibrodentino-and fibro-odontosarcoma

 

BENIGN TUMORS

 

Odontogenic epithelium with mature, fibrous stroma without odontogenic ectomesenchyme

 

- Ameloblastoma, solid/multicystic type

- Ameloblastoma, extraosseous/peripheral type

- Ameloblastoma, desmoplastic type

- Ameloblastoma, unicystic type

- Squamous odontogenic tumor

- Calcifying epithelial odontogenic tumor

- Adenomatoid odontogenic tumor

- Keratocystic Odontogenic tumor *

 

Odontogenic epithelium with odontogenic ectomesenchyme, with or without hard tissue formation

 

- Ameloblastic fibroma

- Ameloblastic fibrodentinoma

- Ameloblastic fibro-odontoma

- Odontoma, complex and compound

- Odontoameloblastoma

- Calcifying cystic odontogenic tumor **

- Dentinogenic ghost cell tumor

 

Mesenchyme and/or odontogenic ectomesenchyme with or without epithelium

 

- Odontogenic fibroma

- Odontogenic myxoma / myxofibroma

- Cementoblastoma

 

Bone related lesions

 

- Ossifying fibroma

- Fibrous dysplasia

- Osseous dysplasia

- Central giant cell lesion (granuloma)

- Cherubism

- Aneurysmal bone cyst

- Simple bone cyst

 

OTHER TUMORS

 

- Melanotic neuroectodermal tumor of infancy

 

* formerly known as OKC (odontogenic keratocyst)

** formerly known as Gorlin cyst

 

Adenomatoid odontogenic tumor

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Also called adenoameloblastoma

Relatively uncommon

70% in teens, remainder from 5 to 50 years, more common in females

Associated with unerupted canine tooth

Slow growing, few/no symptoms

Sites: incisor-cuspid area of maxilla

Xray: well defined unilocular lesion surrounding crown of unerupted or impacted tooth; may be cystic or expansive but not invasive

Treatment: enucleation; does not recur

Case reports: 28 year old man with tumor and impacted tooth, Archives 2003;127:e173

Gross: rounded, well defined fibrous capsule, cystic with focal solid areas; crown of tooth usually projects into cystic cavity

Micro: well circumscribed, central proliferation of ductlike epithelium surrounding small foci of calcification; epithelium may have rosettes, trabecular or cribriform patterns; columnar type cells with basal nuclei and clear cytoplasm may resemble pre-ameloblasts; eosinophilic fibrillar material is present between tumor cells and within ductlike structures; rarely melanin deposition

Micro images: 1-solitary cyst-like lesion, 2-4 ductlike spaces and solid nodules

EM: glandular differentiation

DD: odontogenic cyst, dentigerous cyst

 

Ameloblastic fibroma

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Rare

Usually age 20 or less

Benign, rarely recurs

Xray: variable radiolucent-radiopaque appearance

Treatment: simple curettage

Gross: usually solid

Micro: small islands and cords of markedly attenuated ameloblastic epithelium two cells thick within dense collagenous stroma that is often immature; occasional dentin or cementum production and stellate reticulum; also granular cell variant

DD: ameloblastoma (no connective tissue stroma, has dentin and enamel)

 

Aneursymal bone cyst

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May massively expand the mandible

Young females

Micro: numerous giant cells in connective tissue that lines large sinusoidal spaces

DD: central giant cell granuloma

 

Calcifying epithelial odontogenic tumor

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Also called Pindborg tumor

Rare

Ages 30-49 years

May also occur within gingiva (peripheral tumor)

May be invasive and recur locally, but less aggressive than ameloblastoma

Case reports: metastasis to regional lymph node (J Oral Path 1984;13:310), characterization of amyloid as degenerative keratin filaments (Archives 2000;124:872)

Sites: premolar mandible, often associated with embedded tooth

Xray: resembles dentigerous cyst with occasional small radiopacities within large radiolucent area

Treatment: less aggressive than ameloblastoma

Micro: sheets of polyhedral, eosinophilic squamous epithelial cells with focal psammoma bodies; variable markedly pleomorphic cells with 2-3 nuclei; amyloid bodies (containing degenerated keratin filaments); often scanty stroma, although epithelium / stromal ratio is variable between tumors; clear cell variant has clear vacuolated cytoplasm

Micro images: squamous epithelial cells with calcifications and eosinophilic (amyloid) bodies, keratin

Micro images (Mod Path subscribers): atypical epithelial cells, calcification and amyloid bodies

Positive stains: keratin, Congo red (amyloid bodies)

EM images: fibrillary mesh of amyloid, bundles of tonofilaments

 

Cementifying fibroma

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Mandibular neoplasm of men and women ages 40+ years

May be variant of fibrous dysplasia

Xray: well circumscribed, initially well defined radiolucency, later has central calcifications with radiolucent peripheral rim

Treatment: excision

Micro: cellular fibrous connective tissue with multiple round/oval psammoma-like calcifications resembling cement which may coalesce to form lobulated masses

Cemento-ossifying fibroma: same tumor with trabeculae; some consider it to be related to fibrous dysplasia, AJSP 1995;19:775

 

Cementoblastoma

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Also called true cementoma, benign osteoblastoma

Men and women less than 25 years old

Benign, may stop growing as a heavily calcified jaw nodule, may recur if excised

Xray: dense homogenous mass continuous with tooth root

Gross: large mass of cementum on root of mandibular premolar or molar; tooth viable

Micro: large cementicles (globules) fused to form a mass within proliferative fibrovascular stroma; trabeculae lined by plump osteoblasts

 

Cementoma

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Generic term for periapical cemental dysplasia, central cementifying fibroma, cementoblastoma (true cementoma) or gigantiform cementoma

 

Cherubism

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Hereditary and intraosseous fibrous swellings of jaws

Autosomal dominant, bilateral involvement of mandible and maxilla in young individuals

Treatment: surgery may not be indicated

Micro: similar to central giant cell granuloma; also more delicate fibrovascular stroma without bone formation

 

Desmoplastic fibroma

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Rare, mean 23 years, range 1-75 years