Cysts

There are several cysts in the jaws that have to be considered in the differential diagnosis of apical periodontitis. Although a tentative diagnosis may be made from radiographs, the final diagnosis is always based on histological examination.

A radicular cyst is actually both apical periodontitis and a cyst. The diagnosis cannot be reliably made from a radiograph but requires a histological analysis of the tissue. However, treatment of possible radicular cysts is begun as conservative orthograde treatment of apical periodontitis, sometimes followed by apical surgery.

Other cysts like nasopalatine cysts, periodontal cysts, keratocysts and globulomaxillary cysts are not related to endodontic diseases. However, they may be located near the roots of teeth so that removing the cyst surgically may damage the tooth. Therefore, in some cases, endodontic therapy may be indicated before surgical operation of a cyst.

The traumatic bone cyst (solitary bone cyst) is a non-epithelialised lesion in the bone with unknown aetiology. It is usually asymptomatic but may cause expansion of bone. Traumatic bone cyst may not require treatment but heals spontaneously. However, to establish a diagnosis, a surgical operation is sometimes performed.