An inner cortical mandibular defect may involve any aspect of the mandibular body and/or symphysis. It involves only the lingual cortex of the mandible and thus continuity is not disturbed. The defect includes the associated mucosa but rarely extends through beyond the floor of mouth musculature.
This defect typically results from resection of squamous cell carcinoma of the floor or the mouth or minor salivary gland tumors.