Radicular cyst - Diagnosis

A radicular cyst is impossible to diagnose with certainty without histological investigation. However, teeth with a possible radicular cyst always also have another endodontic diagnosis: apical periodontitis. That is why, from a clinical point of view, such a lesion is usually not a problem even though the final diagnosis of a radicular cyst may be established only after the treatment.

It is often assumed that large, roundish lesions that meet the root surface at a right angle are, with high probability, radicular cysts, but this is not supported by combined histological-radiographic studies. There is evidence suggesting that at least a certain type of radicular cyst (true radicular cyst) usually requires periapical surgery for healing in addition to conservative endodontic therapy (see 'Etiology of radicular cyst' in book 5).

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