The present case report describes a rare case of a lateral and anterior open bite caused by a right trigeminal nerve paresis due to compression of the trigeminal ganglion by a meningioma. Based on the initial diagnosis of TMD, the patient was treated conservatively (also with occlusal splints) for over a year without success, although sensory deficits in the face and tongue, wave-like pain, and a continuous increase in pain symptoms were observed simultaneously. This case report emphasizes the importance of carefully taking the medical history in cases of unclear orofacial pain, supplemented by a clinical examination in which all symptoms and signs can be systematically identified and assigned to a diagnosis.