Oral and mandibular trauma pose barriers to oral thermometry. We sought to determine whether temporal artery (TA) scanning thermometry could be an accurate, noninvasive back up method of thermometry in patients with these types of traumatic injury. We compared 3 techniques of TA scanning, axillary thermometry, and oral thermometry in critical care patients. Our results indicate that TA scanning methods were, at best, comparable with axillary measurements. In addition, the performance of the TA scanners varied with body mass index, whereas axillary readings did not.