Routine diagnosis of this type of fracture should include x-rays taken in
two planes at 90° to each other; the minimum requirement is a PA view and a
CT or digital volume tomography (DVT) imaging may be an alternative. The coronal, sagittal and axial planes each must be checked for the occurrence of fractures.
In order to have a clear overview, a 3-D image is optimal.
3-D reconstruction showing a bilateral mandibular fracture:
anterior body fracture on the right and angle fracture on the left.
Representative slice of a sagittal CT scan series of the same patient.
OPT shows the same patient with bilateral fractures.
DVT (digital volume tomography or cone-beam technology) allows for 3-D analysis and reconstruction on the basis of one data set and carries a radiation dose 1/5 of CT scanning.
Sagittal split fracture
Sagittal fracture lines can be best defined using imaging in tomographic or three dimensional techniques.Sagittal fracture lines can be best defined using imaging in tomographic or three dimensional techniques.
Different view of same fracture. Sagittal condition not obvious.
Axial CT view.
Mechanism of the injury
Simple body fractures most often result from direct impact during physical altercation. Fractures of the mandibular body rarely occur in isolation in the dentate mandible.
The frequency of midbody fractures is rare in comparison to anterior body and posterior body fractures. The latter two locations represent points of weakness due the biomechanics of the mandible. In the anterior body the tooth roots of the canine and the premolars are responsible for decreased mandibular stability. In the posterior body the lever relations close to the angle make up for the weakness.
They are usually combined with fractures in the contralateral hemimandible or with ipsilateral fractures in the ramus/subcondyle.
In contrast, in the edentulous atrophic mandible the body is the most frequent fracture site either unilaterally or bilaterally.