<unk> 's<unk>  is usually discovered by chance during routine dental radiography. Radiographically, it is a well-circumscribed, monolocular, round, radiolucent<unk> , 1–3 cm in size, usually between the inferior alveolar nerve (IAN) and the inferior border of the posterior mandible between the molars and the angle of the jaw. It is one of the few radiolucent lesions that can occur below the IAN. The border is well corticated and it will have no effect on the surrounding structures. Computed tomography (CT) will show a shallow<unk>  through the medial cortex of the mandible with a corticated rim and no soft tissue abnormalities, with the exception of a portion of the submandibular gland. Neoplasms, such as metastatic squamous cell carcinoma to the submandibular lymph nodes or a salivary gland tumour, could create a similar appearance but rarely have such well defined borders and can usually be palpated in the floor of the mouth or submandibular triangle of the neck as a hard mass. CT and clinical exam is typically sufficient to distinguish between this and a<unk> . The<unk>  also tends to not increase in size or change in radiographic appearance over time (hence the term "static bone cyst"), and this can be used to help confirm the diagnosis. Tissue biopsy is not usually indicated, but if carried out, the histopathologic appearance is usually normal salivary gland tissue. Sometimes attempted biopsy of<unk> s reveals an empty cavity (possibly because the gland was displaced at the time of biopsy), or other contents such as blood vessels, fat, lymphoid or connective tissues.<unk> s of the anterior lingual mandible may require biopsy for correct diagnosis at this unusual location. The radiolucent<unk>  here may be superimposed on the lower anterior teeth and be mistaken for an odontogenic lesion. Sometimes the<unk>  may interrupt the contour of the lower border of the mandible, and may be palpable. Sialography may be sometimes used to help demonstrate the salivary gland tissue within the bone.
Stafne defect
Keyhole defect
Double aortic arch
Situs ambiguus
First arch syndrome
Pulmonary hypoplasia
Pulmonary agenesis
Pulmonary atresia