Apart from certain particular types of lesions, the diagnosis of a histologically benign "large mandibular cyst" (paradental cyst, epidermal cyst, ameloblastoma...) should lead to an attempt at conservative treatment: this does not alter mandibular continuity and if possible, the inferior dental neurovascular pedicle, the soft tissues of the buccal lining, and the dental organs. It is finally the gross pathological findings and if necessary the results of an extemporaneous histological examination that will supply the information leading to the choice of the best type of treatment: marsupialization, enucleation, curettage, "pressure curettage", uninterrupting resection. This attitude requires prolonged postoperative radiological supervision and does not exclude the need for an interrupting resection in unfavourable cases at a later date.