Risk Stratification

Do the patient’s teeth meet abnormally (i.e. malocclusion)? A number of clinical findings have been identified to correlate with the presence of a mandibular fracture. In one study, malocclusion, trismus, facial asymmetry and a positive tongue blade test were all strongly associated with a fracture [8].

A clinical decision rule for radiography in mandibular trauma has also been developed, namely:

The Manchester Mandibular Fracture Decision Rule [9]
1. Do the patient’s teeth meet abnormally (i.e. malocclusion)?
2. Is the patient unable to open his/her mouth normally (i.e. trismus)?
3. Does the patient have any broken teeth?
4. Does the patient report pain while their mouth is closed?
5. Is there a step deformity?
If yes to any of the above, then request mandibular x-ray

The presence of any of these five factors produced a 100% sensitive rule for x-ray.

The authors of the rule report that its use could reduce the number of x-rays done in mandibular trauma by 30% and that it outperformed clinicians’ diagnostic ability.

Learning Bite

The use of a decision rule for mandibular trauma is highly sensitive and may reduce the number of x-rays done by 30%.