A Case of Lockjaw by Penetration of Deciduous Incisors into the Lower Lip

Abstract

In recent years, the number of children visiting pediatric dental clinics complaining of physical dental trauma has been increasing. In fact, our clinic has treated many children with such complaints. In this article, we report a case of lockjaw by penetration of the mandibular deciduous incisors and maxillary deciduous canines into the lower lip.

The patient was a 3-year-old boy who was referred to our department for a more detailed examination for lockjaw caused by physical trauma. He had been unable to open his mouth for a week after the injury, making it difficult to eat. Penetration of the mandibular deciduous incisors and maxillary deciduous canines into the lower lip and root fracture of the mandibular left deciduous central incisor were confirmed by a simple CT scan of the head and neck. When an attempt was made to open the mouth under intravenous sedation, the deciduous canines on both sides of the maxilla came off from the lower lip, and an opening of about one finger width became possible. Therefore, the lower lip was debrided and lockjaw was released. Upon follow-up observation, the patient's lower lip wounds had healed, the lockjaw improved, and he was able to consume food.

Most cases of lockjaw caused by physical trauma are due to damage to hard tissue; however, as this case indicated, lockjaw can also be caused by damage to soft tissue.