Where is the jaw most likely to break?
The lower jaw is shaped like a horseshoe, so a blow to one point creates tension on the opposite side. That is why approximately half of the victims have two or more fractures. The weakest areas are the area of the angle of the jaw, especially with an unerupted wisdom tooth, the canine area, the chin and the condylar process, which is involved in the temporomandibular joint. Fractures of the condylar process are especially important: they affect mouth opening and, if not treated correctly in children, impair jaw growth.
- Fracture of the angle of the jaw, often in the area of the wisdom tooth
- Fracture of the condylar process with disruption of the joint
- Fracture of the chin
- Fracture of the jaw body in the dentition
- Double and multiple fractures
- Displaced fractures due to traction of the masticatory muscles
Symptoms
The first thing a person notices is that the teeth no longer close together as before: a gap appears between the teeth or the jaw moves to the side. Opening the mouth is painful and limited, speech and swallowing are difficult. In the mouth, a bruise is visible on the mucous membrane under the tongue - a characteristic sign of a fracture. There may be mobility of fragments with careful rocking, a step in the dentition, ruptures of the mucous membrane. Numbness of the lower lip and chin indicates damage to the inferior alveolar nerve, which runs inside the jaw. Facial swelling increases quickly.
- Malocclusion and jaw displacement to the side
- Pain when opening the mouth and chewing
- Bleeding on the mucous membrane under the tongue
- Stepping and mobility in the dentition
- Numbness of the lower lip and chin
- Facial swelling and difficulty speaking
Diagnostics
The doctor examines the face and oral cavity, evaluates the bite, mobility of fragments, sensitivity of the lip and the volume of mouth opening. An X-ray of the lower jaw in several projections allows one to see most fractures, but if damage to the condylar process, multiple fractures and concomitant injuries of the facial skeleton are suspected, the main method becomes computed tomography with three-dimensional reconstruction. Be sure to exclude traumatic brain injury and damage to the cervical spine, since the mechanism of injury is often common. The dentist evaluates the condition of the teeth at the fracture line.
- Oral examination and bite assessment
- X-ray of the lower jaw in several projections
- CT scan of the facial skeleton with three-dimensional reconstruction
- X-ray of the skull with combined trauma
- Ruling out traumatic brain injury
- Assessment of teeth in the fracture zone by a dentist
Treatment
The task is to return the fragments to the correct position and hold them, restoring the previous bite. For non-displaced fractures and some fractures of the condylar process, a conservative approach is used: dental splints with intermaxillary fixation with rubber bands for 3–5 weeks, a gentle diet, and careful oral hygiene. In case of displacement, multiple fractures and fractures in the dentition, osteosynthesis is performed with titanium plates through access from the oral cavity: this allows you to start opening your mouth and eating earlier. Teeth in the fracture line are preserved if they do not interfere with the comparison and are not destroyed. Antibiotics are prescribed by the doctor.
- Reposition of fragments and restoration of bite
- Dental splints with intermaxillary fixation
- Osteosynthesis with titanium plates and screws
- Removal of a tooth from the fracture line according to indications
- Antibacterial therapy for open fractures
- Careful oral hygiene and rinsing
Nutrition, recovery and complications
While the jaws are fixed, the food is liquid and semi-liquid: pureed soups, pureed porridges, fermented milk products, mixtures, if necessary, through a straw. It is important not to lose weight and get enough protein. Oral hygiene is critical: rinsing after every meal is required. After the fixation is removed, the diet is gradually expanded and exercises are performed to restore mouth opening. Possible complications include suppuration in the fracture area, persistent malocclusion, limited mouth opening, prolonged numbness of the lower lip, and in children, impaired jaw growth. Follow-up inspections are required.
- Liquid and pureed food for the fixation period
- Sufficient protein and calories
- Rinse after every meal
- Mouth opening exercises after splint removal
- Bite control at the dentist
- Monitoring jaw growth in children