Accessory pterygoid fovea of the human mandibular condyle

Background: The pterygoid fovea on the mandibular neck is superomedial to the mandibular notch and serves to attach the lateral pterygoid muscle. Clinical presentation: During a retrospective cone beam computed tomography study, a 67-year-old male patient was found to exhibit a peculiar variant that contradicted normal anatomy. The patient's mandibular condyles were asymmetrical in terms of their shapes and sizes, although their lateral poles (lateral condylar tubercles) were both prominent. On the left side, the lateral condylar tubercle had a second, or accessory, pterygoid fovea, which was located outside the mandibular notch. Further, the left lateral pterygoid muscle was attached to the entire width of the mandibular condyle, including the accessory fovea. Clinical significance: Such rare anatomical variants lead to asymmetrical temporomandibular joints, although their occurrence has not previously been reported. Thus, they should be further documented in clinical studies of temporomandibular joint dysfunction.