While giving IANB nerve block, postoperatively the patient complains of trismus due to:
Trismus is inability to open mouth due to muscle spasm. It is caused by injection into medial pterygoid muscle resulting in hematoma formation or infection. The application of heat and administration of antibiotics relieve the symptoms.
Injection into buccinator
Injection into parotid capsule
Injection into medial pterygoid
Paralysis of nerve