Case #4

A 30-year-old female visited a dental office for a routine check-up and prophylaxis. Radiographic examination revealed a large radiolucency in the mandibular premolar-molar area.

Apr 1st, 1997

A 30-year-old female visited a dental office for a routine check-up and prophylaxis. Radiographic examination revealed a large radiolucency in the mandibular premolar-molar area.

Joen Iannucci Haring, DDS, MS

History

The patient denied any history of signs or symptoms associated with the mandibular premolar-molar region. The patient appeared to be in a general good state of health, with no significant medical history. The patient`s dental history included regular dental examinations and routine dental treatment. At the time of the dental appointment, the patient was not taking medications of any kind.

Examinations

The patient`s vital signs were all found to be within normal limits. Examination of the head and neck region revealed no enlarged or palpable lymph nodes. Examination of the oral soft tissues revealed no unusual findings, no bony abnormalities, and no tooth anomalies.

After a thorough clinical examination, four bite-wing radiographs, selected periapical films and a panoramic film were ordered. Examination of the panoramic radiograph revealed a large, unilocular radiolucency with a well-defined border extending from the mesial root of tooth #19 to the distal surface of the root of tooth #21 (see radiograph).

Following the radiographic examination, the teeth adjacent to the lesion were pulp tested for vitality with an electric pulp tester. All teeth tested vital. No expansion or bony changes were noted in the area of the lesion.

Clinical diagnosis

Based on the clinical and radiographic information available, which of the following is the most likely diagnosis?

* apical periodontitis

* ossifying fibroma

* calcifying odontogenic cyst

* osteoma

* benign cementoblastoma

Diagnosis

_ ossifying fibroma

Discussion

The ossifying fibroma (also known as the cementifying fibroma or the cemento-ossifying fibroma) is an uncommon neoplasm. This lesion consists of fibrous tissue mixed with variable amounts of calcified tissue resembling bone or cementum, or a combination of both. The ossifying fibroma is osteogenic in origin.

Clinical features

Although the ossifying fibroma may occur over a wide age range, individuals in the third and fourth decades of life are most often affected. Females are affected far more frequently than males (5:1). The ossifying fibroma occurs more often in the mandible than in the maxilla and 90 percent of all cases are seen in the mandibular premolar-molar area.

The ossifying fibroma is never seen in association with an impacted tooth and the teeth adjacent to this lesion are vital. The smaller lesions are asymptomatic and, therefore, are only discovered during routine radiographic examination. The larger lesions may cause a painless swelling and expansion of bone. Numbness is seldom a feature.

Radiographic features

The ossifying fibroma is easily detected on a periapical or panoramic radiograph. When viewed on a dental radiograph, the ossifying fibroma typically appears as a well-circumscribed unilocular radiolucency. Although this lesion most often appears as a radiolucency, it may also present as a radiolucency containing scattered radiopacities. The degree of radiopacity varies depending on the amount of calcification present. The size of the ossifying fibroma ranges from small to large. With large lesions, splaying of the adjacent teeth may be noted on the dental radiograph.

Diagnosis

A biopsy is necessary to establish the diagnosis of an ossifying fibroma. The lesion cannot be diagnosed from a radiograph alone. Microscopically, the lesion exhibits fibrous tissue with varying degrees of cellularity containing calcified material.

Treatment

The treatment for the ossifying fibroma includes enucleation and curettage. Because the lesion is well-defined, enucleation is relatively easy. The prognosis for an individual with an ossifying fibroma is very good. This lesion is unlikely to recur following removal. In addition, there is no evidence of malignant potential.

Joen Iannucci Haring, DDS, MS, is an associate professor of clinical dentistry, Section of Primary Care, The Ohio State University College of Dentistry.

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