Electronic thermography of normal facial structures: a pilot study

New electronic thermographic instruments capable of routine clinical examination need to be evaluated for their potential as a diagnostic aid in dentistry. This study assessed thermal symmetry of the face and neck in 20 normal subjects with the use of frontal and lateral views, at 1.0 degree C and 0.5 degree C sensitivity, under controlled conditions. Electronic thermographic images were analyzed for thermal symmetry, by means of a grid matching technique, in 12 anatomic regions and the overall face. Results indicated that thermal symmetry for the entire face was high (70.2%). The 12 specific facial areas demonstrated varying levels of thermal symmetry. Regions of high symmetry on frontal projections included the anterior portion of the neck (82.0%), the TMJ (80.0%), the lower lip (78.6%), and the upper lip (77.3%). The temporal region (46.7%) was found to be of relatively low thermal symmetry. Regions of high symmetry on lateral projections included the nasal region (69.5%) and the inframandibular region (67.0%). The posterior neck region (44.2%) was found to be of relatively low thermal symmetry. In general, normal subjects demonstrated high levels of thermal symmetry over most regions of the face. This pilot investigation is an early step in the evaluation of electronic thermography for future use in dentistry.