When yawning, the chin fell off and Botox was injected to save it.

1 77-year-old male, suffering from diabetes and heart disease, slight stroke and poor circulation of lower limbs. Recently, at a family gathering, I couldn't close my mouth because I laughed so hard. Although the doctor reset my chin urgently, since then, as long as the old man didn't pay attention and yawned, I couldn't close my mouth, which became a frequent symptom of "dropping my chin", which troubled patients and their families very much.

Dislocation of chin, commonly known as "jaw drop", that is, dislocation of temporomandibular joint, often bothers patients and their families. (Photography/Huang Zhiwen). Dr. Xu Weikai, dentist of oral and maxillofacial surgery at St. Martin Catholic Hospital, pointed out that the commonly known "jaw drop" is temporomandibular joint dislocation. Temporomandibular joint is the joint that controls the movement of chin, and its movement mode is unique among all joints. In addition to the common "Chu Jiu movement" of limbs, you can also slide forward in the joint fossa to make your mouth open wider.

Under normal circumstances, there is a ligament behind the joint to pull the joint to avoid excessive sliding; However, such as external force impact or muscle disorder, it is possible to make the joint move forward excessively. When the joint bulges out, the joint will get stuck and the surrounding muscles will be stiff, so that the joint cannot return to the dislocated position.

Pay attention to "dropping your chin" often.

Dr. Xu Weikai said that after the dislocation, the doctor pushed his chin back, and when the patient later opened his mouth or yawned, he held his chin with his fist. After about two months' rest, most of them can return to normal. However, some people, especially those suffering from stroke or dementia, will often suffer from "chin drooping" in the future, even if their chin is reset.

This is because the joints and ligaments are overstretched and relaxed, and these people's brains are damaged and lose the original brain feedback mechanism, which will make the muscles overexert and dislocate the chin; In severe cases, it may even develop into chronic recurrent temporomandibular joint dislocation. If the mouth is a little wider, the chin will dislocate, which is unbearable.

Treatment of "jaw drop" with botulinum toxin

In the past, such patients were treated by surgery, including increasing or decreasing the height of the joint protuberance. However, if the patient is older and has chronic diseases such as stroke, the risk taken in the operation is higher and the family members will not accept it.

Now it can be treated conservatively with botulinum toxin. Botulinum toxin can relax muscles that are already too tense. Botulinum toxin injection into lateral pterygoid muscle can reduce the strength of joint flexion and the probability of dislocation.

The doctor reminded me:

Botox injection for the treatment of frequent jaw dislocation is not completely risk-free. If Botox is injected too deeply, it may cause velopharyngeal atresia, leading to nasal sounds or coughing when drinking water. Therefore, it is reminded that Botox should be managed by doctors who are familiar with this part of the structure.