An oral and maxillofacial surgeon diagnoses conditions involving the mandible, maxilla, temporomandibular joint (TMJ) and the broader craniofacial region. Common presentations include temporomandibular disorders (pain, clicking, locking), functional mandibular conditions, skeletal malocclusion, the consequences of facial trauma, and other maxillofacial conditions frequently identified on referral from a dentist or GP. Diagnosis is not based on a single symptom, but on a comprehensive assessment that combines clinical history, examination, and targeted investigations.