Parotid Gland
The gland located underneath the temporomandibular joint (TMJ) is the parotid gland. 1
Anatomical Relationship
The parotid gland sits in close anatomical proximity to the TMJ, which creates important clinical implications for diagnosis and treatment:
- Masses in the parotid region can be difficult to distinguish from TMJ pathology, as both present with preauricular swelling and may cause similar symptoms 2, 3
- The parotid gland is located in the parotid/buccal area, and fat loss in this region following mandibular reconstruction leads to facial asymmetry 1
- Ectopic parotid tissue (choristomas) can even be found within TMJ ligaments and capsules themselves, with up to 33 independent salivary gland structures documented in damaged TMJ soft tissues 4
Critical Diagnostic Pitfall
A major clinical trap is misdiagnosing parotid pathology as TMJ dysfunction, which can delay appropriate cancer treatment:
- Parotid tumors can mimic TMJ disorders by presenting with pain, clicking, limited jaw movement, and preauricular swelling 2, 3, 5
- Multiple case reports document parotid malignancies initially misdiagnosed and treated as TMD, resulting in dangerous treatment delays 5
- TMJ ganglion cysts have been mistaken for parotid tumors in the preoperative setting, with the correct diagnosis only made during surgical exploration 3, 6
Key Distinguishing Features
When evaluating a mass in this region, consider:
- Parotid tumors that change size or position with jaw movement should raise suspicion for TMJ ganglion rather than parotid neoplasm 3
- Preauricular lymph nodes can also be found in TMJ surgical specimens, with hyperplastic nodes showing nonspecific inflammatory changes 4
- Proper imaging (ultrasound for salivary glands, MRI/CT for TMJ) is essential to differentiate these anatomically overlapping structures 1