An osteoma is a benign tumor essentially restricted to the craniofacial skeleton. Osteomas occur most frequently in the frontal, ethmoid, and maxillary sinuses, and rarely affect the glenoid fossa. Osteomas are usually pain-free and remain silent, ie, symptom-free, for many years but may lead to occlusal changes. The report describes the case of an adult man with an osteoma who presented with a chief complaint of malocclusion and who was misdiagnosed. The case points to the diagnostic reasoning necessary to arrive at a correct diagnosis, especially when signs and symptoms, as well as pathology, are rare, eg, not familiar to the clinician. Schlagwörter: bone neoplasms, diagnostic errors, osteoma, temporomandibular joint, temporomandibular joint disorders