A 40-yr-old man was referred for the treatment of a large bony lesion of the mandible proximal to the root apices of the lower left first molar. Treatment had been done 7 to 8 yr previous to the examination, and the fill appeared to be adequate. Treatment was curettement of the lesion, apical curettage, and filling of the lesion with sterile freeze-dried bone. The patient was seen 6 months later and reported that he had been asymptomatic and was very pleased with the treatment. A postoperative radiograph was taken at that time and it showed that there had been an ingrowth of healthy bone into the bony lesion and that only a small radiolucency at the mesial root remained. In only 6 months, a very large lesion of the mandible had almost completely resolved after using freeze-dried bone to act as a matrix for the ingrowth of new bone tissue. At 7 months postoperatively, another radiograph was taken which showed continued healing.