Marginal mandible, full thickness (double cortical)

Bicortical mandibular rim defect

A bicortical mandibular rim defect may involve any aspect of the mandibular body and/or symphysis. It involves only the superior rim 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 superficial squamous cell carcinoma of the alveolar gingiva or minor salivary gland tumors.