Thyroid & Adrenal
Most common type of cyst in jaw
|C||Solitary bone cyst|
a. Odontogenic cysts are defined as epithelial-lined structures derived from odontogenic epithelium.
b. Most odontogenic cysts are defined more by their location than by any histologic characteristics.
c. Accordingly, the surgeon must provide the pathologist with appropriate history and radiographs when submitting such specimens for examination.
a. A periapical (radicular) cyst is the most common odontogenic cyst.
b. The usual etiology is a tooth that becomes infected, leading to necrosis of the pulp.
c. Toxins exit the apex of the tooth, leading to periapical inflammation. This inflammation stimulates the Malassez epithelial rests, which are found in the periodontal ligament, resulting in the formation of a periapical granuloma that may be infected or sterile. Eventually, this epithelium undergoes necrosis caused by a lack of blood supply, and the granuloma becomes a cyst.
d. The lesions are not usually clinically detectable when small but most often are discovered as incidental findings on radiographic survey.
e. Radiographically, distinguishing between a granuloma and a cyst is impossible, although some say that if the lesion is quite large it is more likely to be a cyst.
f. They both present as radiolucent lesions in association with the apex of a nonvital tooth.
g. Although these cysts arise from a mature resting epithelium and thus have a relatively low growth potential, a squamous cell carcinoma occasionally may arise de novo in a radicular cyst, thus the recommendation for histopathologic examination of all tissues removed.