Male age 40, cyst in the front of the mandible, range of root #31(24) and #32(23). There was pain, swelling and active buccal fistula. Enucleation of the cyst and resection with retrograde and filling (MTA) of roots #31(24) and #32(23). Augmentation was done with Bond Apatite®. The fistula disappeared spontaneously in two weeks. The patient’s pain and discomfort disappeared completely with no clinical or pathological symptoms.