noun
trismus; lockjaw
Medical term for the inability to open the mouth fully, often due to muscle spasm. Used in clinical contexts.
破傷風の初期症状として牙関緊急が現れることがある。
Trismus can appear as an early symptom of tetanus.
歯科治療後に一時的な牙関緊急を訴える患者もいる。
Some patients complain of temporary lockjaw after dental treatment.
開口障害 is a broader term for any difficulty in opening the mouth, while 牙関緊急 specifically refers to trismus caused by muscle spasm.
Compound of 牙関 (gakan, 'jaw joint') and 緊急 (kinkyū, 'urgent' or 'tight'), literally 'jaw joint tightness'. The exact historical derivation is uncertain; the term is used in modern medical Japanese.