An 80-year-old patient presents with a midline tumor of the lower jaw, involving the alveolar margin. He is edentulous. Treatment of choice is:

Mandibulectomy Marginal mandibulectomy Segmental mandibulectomy - Conservative mandibulectomy - Refers to paial excision of the superior poion of mandible in veical phase - Inner coical surface and a poion of underlying medullary cavity is excised - Preserve mandibular continuity - Indicated when tumor lies within I cm of the mandible or abuts the periosteum without evidence of direct bony invasion - Entire through and through segment of mandible is resected - Results in mandibular discontinuity - Require major reconstructive procedure for cosmetic and functional purposes - Indications: 1. Invasion of medullary space of mandible 2. Tumor fixation to occlusal surface of mandible in edentulous patients 3. Invasion of tumor into the mandible mandibular or mental foramen 4. Tumor fixed to the mandible.