The purpose of this article was to report the clinical, radiographic, and histological findings about a case of a young woman affected by a mandibular odontogenic myxoma. Conservative tumor resection was followed by immediate reconstructive treatment using fresh-frozen human bone graft, instead of autologous bone graft, as material for bone regeneration. Odontogenic myxoma, according to the World Health Organization, is classified as a benign tumor of mesenchymal origin whether or not containing odontogenic epithelium. Radiological and histological examination of the lesion confirmed the presence of an odontogenic myxoma, which was 21.2 mm high and 47.6 mm long; the lesion underwent biopsy evaluation before enucleation. According to literature and with the aim of a patient free of disease, conservative enucleation of the lesion was performed. The residual bone defect was filled with fresh-frozen bone allograft. At 6 months after surgery, no evidence of major complications was observed; the computed tomography scan revealed effective bone regeneration through the grafted area. The use of fresh-frozen bone allograft, thanks to its osteoinductive and osteoconductive properties, may represent an optional choice for reconstruction of bone defects after jaw tumor removal.