An 11-year-old male visited a dentist for a routine checkup. Radiographic examination revealed a lesion involving an erupted molar in the right maxilla.
Joen Iannucci Haring, DDS, MS
The patient did not have an erupted six-year molar present in the maxillary right quadrant. The patient denied any history of signs or symptoms associated with this region. The patient appeared to be in a general good state of health, with no significant medical history. The patient`s dental history included sporadic dental examinations and routine dental treatment. At the time of the dental appointment, the patient was not taking medications of any kind.
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 were noted.
The patient`s most recent bite-wing radiographs were dated one year earlier, and no panoramic radiograph had been exposed to date. After a thorough clinical examination and a review of the patient`s medical and dental histories, a panoramic radiograph and four bite-wing films were ordered.
Examination of the panoramic radiograph revealed a mixed radiolucent-radiopaque lesion in the right maxilla. The lesion was seen in association with an unerupted tooth #3 (see radiograph).
Based on the clinical and radiographic examination available, which one of the following is the most likely diagnosis?
* ameloblastic fibroma
* ameloblastic fibro-odontoma
* adenomatoid odontogenic tumor
* calcifying odontogenic cyst
The ameloblastic fibro-odontoma is a benign odontogenic tumor of epithelial and connective tissue origin. This neoplasm evolves from elements that are normally involved in the formation of teeth. The actual histogenesis of this lesion is uncertain. The ameloblastic fibro-odontoma is considered to be an uncommon tumor.
The ameloblastic fibro-odontoma is most often seen in young patients. The average age of a patient with an ameloblastic fibro-odontoma is 10; approximately 90 percent of cases occur under the age of 15. There is no gender predilection. The ameloblastic fibro-odontoma is seen in association with the crown of an unerupted or impacted tooth. The mandible and maxilla are affected with equal frequency. The ameloblastic fibro-odontoma is a slow-growing, solitary lesion. Pain is usually not a feature. Bony expansion may or may not be present, depending on the size of the lesion. Only large lesions are associated with swelling of the jaws.
The ameloblastic fibro-ondontoma may appear as a unilocular or multilocular radiolucent lesion with well-defined borders. In addition, the ameloblastic fibro-odontoma may have a radiopaque component. A variable amount of calcified material with the radiodensity of tooth structure (enamel and dentin, for example) is present. The calcified material may appear as a solid mass or multiple small radiopacities. When viewed on a dental radiograph, this lesion is typically seen in association with an impacted or unerupted tooth.
The ameloblastic fibro-odontoma cannot be diagnosed from its radiographic appearance alone. The ameloblastic fibro-odontoma, like other lesions seen on a dental radiograph, should be documented in the patient record and described in terms of appearance, location, and size. Biopsy and surgical removal must be recommended to the patient.
Biopsy and histologic examination of the lesion is necessary to make a definitive diagnosis. Histologically, the ameloblastic fibro-ondontoma resembles the ameloblastic fibroma with the exception of the presence of calcified areas that resemble enamel and dentin. Other lesions that may be considered in the differential diagnosis for the ameloblastic fibro-ondontoma include ameloblastic fibroma (RDH, January 1998), the adenomatoid odontogenic tumor (RDH, July 1994), calcifying odontogenic cyst (RDH, July 1997), and the odontoma (RDH, July 1990).
The ameloblastic fibroma is a tumor and must be treated. Surgical removal of the lesion is the treatment of choice. Recurrence following surgical removal is unusual. In extremely rare cases, the malignant ameloblastic fibrosarcoma may develop after curettage of the ameloblastic fibro-odontoma.
Joen Iannucci Haring, DDS, MS, is an associate professor of clinical dentistry, Section of Primary Care, The Ohio State University College of Dentistry.