Ameloblastomas are rare, typically benign tumors that originate in odontogenic epithelial tissue (tissue of the jaw, usually near the third molar). These tumors are rarely metastatic (they rarely spread to other parts of the body) and they rarely develop into a malignant growth, but they can result in lesions that lead to severe abnormalities in the jaw and face.
Neoplastic tissue associated with an ameloblastoma can also easily infiltrate and damage the surrounding bone structures. Thus, wide surgical excision is often necessary to treat and/or reduce symptoms of this disorder.
Ameloblastoma Signs and Symptoms
An ameloblastoma is often accompanied by the presence of unerupted teeth. Wisdom teeth account for almost all unerupted teeth in adults. The patient may experience, as a result of the growth, loose teeth, ulcers in the mouth, periodontal (gum) disease, swelling, and facial deformities if the lesions are severe enough.
These lesions can occur in both the mandible (lower jaw) and maxilla (upper jaw), but 75% of them occur in the ascending ramus of the mandible (the part of the jaw bone that forms the joint with the skull). When ameloblastomas are present in the maxilla, they have a tendency to spread into the sinus cavities and the floor of the nose, resulting in pain and deformities.
Furthermore, because the progression of an ameloblastoma is usually very slow, periosteum (a membranous tissue that invests all bones) often has enough time to create a thin shell of bone around the expanding neoplastic tissue. This shell will crack when examined by touch and/or when the tumor has expanded enough to puncture the bone. This cracking of the bone is known as crepitus and is a major factor in the diagnosis of an ameloblastoma.
Learn more about the types and symptoms of Ameloblastoma.
Ameloblastomas are diagnosed using a combination of radiographic examination and biopsy. In radiographic examinations, an ameloblastoma reveals itself as a lucent region in the bone. It is said that the appearance of an ameloblastoma resembles a soap bubble in such examinations. Biopsied tissue confirms the diagnosis.
Typically, ameloblastomas resist radiation and chemotherapy, making surgery the most common and most curative treatment. Unfortunately, this tumor often invades the jawbone through the porous marrow (this invasion is not the same as metastasis), commonly resulting in the surgical removal of adjacent bone matter.
Even though an ameloblastoma is not a cancer, surgical removal of the growth is treated similar to that of a cancer. This means that wide surgical margins, far from diseased tissue, are usually required for a good prognosis. Recurrence is frequent with ameloblastoma.