ODONTOMA

the most common types of odontogenic tumors

(hamartomas) rather than true neoplasm

When fully developed, consist…….

a conglomerate mass of enamel and dentin, which bears no anatomic resemblance to a tooth.

compound odontoma :multiple, small toothlike structures

complex odontoma: compound odontoma

complex odontoma

A mixed odontogenic tumor

Most odontomas are detected during the first two decades of life.

Clinical Features

asymptomatic

relatively small and seldom exceed the size of a tooth in the area

complex odontomas occur more often in the molar regions of either jaw.

the compound type is more often seen in the anterior maxilla

Occasionally within the gingival soft tissues

Multiple toothlets preventingthe eruption of the mandibular cuspid.

Complex odontoma.

A large radiopaque mass is overlying the crown of the mandibular right second molar

surrounded by a narrow radiolucent rim.

Some small odontomas are present between the roots of erupted teeth

radiographically confused with an osteoma

The radiographic findings are usually diagnostic

Compound odontoma

Histopathologic Features

consists of multiple structures resembling small, single-rooted teeth, contained in a loose fibrous matrix.

compound odontoma

a misshapen tooth

Tubular dentin H&E(x100)Pulp-like tissues

a small Tooth like stracture

Enamel Matrix

The spaces may contain small amounts of enamel matrix or immature enamel.

Complex odontomas consist largely of mature tubulardentin.

This dentin encloses clefts or hollow circular structures that contained the mature enamel.

Small islands of eosinophilic-staining epithelial ghost cells are present in about 20% of complex odontomas.(Keratinization or cell death from the local anoxia.)

A thin layer of cementum is often present about the periphery of the mass.

Tubular dentin

a dentigerous cyst may arise from the epithelial lining of the fibrous capsule of a complex odontoma.

Odontomas are treated by simple local excision.

prognosis is excellent.

Treatment and Prognosis

the calcifying odontogenic cyst may beassociated with odontomas (20%)