1. ODONTOMA

2. the most common types of odontogenic tumors
A mixed odontogenic tumor
(hamartomas) rather than true neoplasm
When fully developed, consist…….
compound odontoma :multiple, small toothlike structures
complex odontoma:
a conglomerate mass of enamel and dentin, which bears no anatomic resemblance to a tooth.
compound odontoma
complex odontoma

3. Clinical Features
Most odontomas are detected during the first two decades of life.
asymptomatic
relatively small and seldom exceed the size of a tooth in the area
the compound type is more often seen in the anterior maxilla
complex odontomas occur more often in the molar regions of either jaw.
Occasionally within the gingival soft tissues

4. Compound odontoma
Complex odontoma.
The radiographic findings are usually diagnostic
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
Multiple toothlets preventing
the eruption of the mandibular cuspid.
radiographically confused with an osteoma

5. Histopathologic Features
compound odontoma
consists of multiple structures resembling small, single-rooted teeth, contained in a loose fibrous matrix.
a misshapen tooth

6. a small Tooth like stracture
Enamel Matrix
H&E(x100)
Pulp-like tissues
Tubular dentin

7. Complex odontomas consist largely of mature tubular dentin.
This dentin encloses clefts or hollow circular structures that contained the mature enamel.
The spaces may contain small amounts
of enamel matrix or immature 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.

8. Tubular dentin

9. Treatment and Prognosis
a dentigerous cyst may arise from the epithelial lining of the fibrous capsule of a complex odontoma.
the calcifying odontogenic cyst may beassociated with odontomas (20%)
Odontomas are treated by simple local excision.
prognosis is excellent.