Thermographic Assessment of Inferior Alveolar Nerve Injury in Patients With Dentofacial Deformity

Purpose

The purpose of this study was to evaluate the injury and recovery of the inferior alveolar nerve in orthognathic patients at 1 and 4 weeks after surgery using electronic thermography.

Materials and Methods

Twenty subjects with Class III dentofacial deformity were studied. All patients underwent bilateral sagittal split ramus osteotomy. To image the temperature of the face, 1 anteroposterior view and 1 lateral view were taken from both the right and left sides. Similar images were taken at 1 and 4 weeks after surgery. The control was the presurgical temperature of the 20 patients who showed unilateral or bilateral nerve damage after surgery.

Results

In the patients with unilateral nerve damage (n = 14), on the anteroposterior views, the temperatures of the mentum on the 2 sides differed by 0.64°C at 1 week after surgery, and the difference decreased to 0.23°C at 4 weeks after surgery. On the lateral images, the differences in temperature between the mentum areas were 0.10°C at 1 week and 0.27°C at 4 weeks after surgery. In the patients with bilateral nerve injury (n = 6), on the anteroposterior views, the temperatures of the mentum on the 2 sides differed by 0.20°C at 1 week after surgery and 0.13°C after 4 weeks. On the lateral views, the differences were 0.18°C at 1 week and 0.34°C at 4 weeks after surgery. Using the repeated measurement analysis method, the anteroposterior view showed statistically significant results in the patients with unilateral nerve damage.

Conclusion

The infrared body temperature method is an objective method that can be applied as a supplemental diagnostic method for inferior alveolar nerve injury.