[Orthograde (non-surgical) treatment of large apical lesions].

Many clinicians believe that large apical lesions, sometimes as small as ø ≥1 cm, should be treated surgically, as the size of the lesion leads to the assumption that it is a cyst that cannot be treated conventionally. According to Nair (1996), however, only 9% of all lesions are true radicular cysts. In the surgical treatment of large endodontic lesions, it is difficult to achieve good bony healing. Sometimes only scar tissue healing occurs (classification according to Rud and Molven). Due to the surgical procedure, a resti tutio ad integrum does not always result with regard to osseous healing even after the placement of a membrane.