Sir, the mandible is the most commonly fractured facial bone in humans and is easily identified by a plethora of signs and symptoms. However, radiographic imaging is required to confirm and assess the position and the severity of the fracture. Depending on the resources available to the hospital, a variety of imaging techniques are currently employed.
The mandibular series (MS) and the orthopantogram (OPG) are the most common plain radiographs used in diagnosis. Three dimensional imaging with computed tomography (CT) is also employed.
The MS consists of a right and left lateral oblique, a reverse Towne projection and an anterior-posterior mandibular view (PA).1 These plain radiographs are technique sensitive, time consuming, difficult to interpret and expose patients to high levels of radiation.2 In comparison to the MS, OPG radiographs are superior in identifying mandibular fractures.2,3 The MS offers one advantage over the OPG: they are more suitable for uncooperative patients and patients who unable to stand upright and motionless for short periods.
The OPG and PA are generally considered the gold standard due to their low cost and ease of technique. Some hospitals do not have access to an OPG machine or these are not available for use outside of normal working hours. Therefore despite the advantages of an OPG, patients attending overnight or presenting to smaller emergency departments are having an MS for suspected mandibular fractures.
Although the MS can be diagnostic, it is our experience that many patients receive a further OPG once they reach the oral and maxillofacial referral centre. This aids planning pre-operatively and provides a baseline radiograph for post-operative follow up. However, this exposes the patient to unnecessary and high doses of radiation. This can be avoided if patients with a high clinical suspicion for a mandibular fracture are referred to the nearest oral and maxillofacial hospital for the appropriate radiographs.
Although CT imaging provides more detail, it involves higher costs, more radiation exposure and the possibility of artefact generation.3 Therefore, CT imaging may be reserved for patients with head injuries or multiple maxillofacial fractures and patients with a high suspicion for a mandibular fracture which was not identified on 2D imaging.
Due to the multitude of disadvantages of the MS, we propose that patients with a high clinical suspicion for a mandibular fracture should have a minimum of an OPG and a PA to confirm the diagnosis. If an OPG machine is not available, a referral to an appropriate centre should be considered. This would limit the patient’s radiation exposure and also standardise radiographic examinations.
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Devine, C., Srinivasan, B. & Ramchandani, P. Dental radiography: Plain film radiographs.
Br Dent J 222, 910 (2017). https://doi.org/10.1038/sj.bdj.2017.522