QUANTITATIVE SENSORY TESTING IN THE OROFACIAL REGION

Quantitative sensory testing (QST) is applied to evaluate somatosensory nerve fiber function. Compared to the spinal system, there are only very few investigations in the orofacial region. Thirty male and 30 female volunteers (19 to 62 years) participated in the study. All subjects were tested bilaterally in the innervation areas of infraorbital (i), mental (m) and lingual (l) nerves. Thermal detection and pain thresholds (peltier-type thermode), mechanical detection threshold (von-Frey-filaments), mechanical pain threshold and sensitivity, wind-up ratio (pinprick stimuli), dynamic mechanical allodynia, vibration detection threshold (tuning fork) and pressure pain threshold (spring mounted pressure meter) were determined. There was no significant right-to-left side difference for any of the QST parameters. Many parameters were region specific and age- related. Thermal sensitivity was higher over upper lip, followed by lower lip and tongue. Women showed higher sensitivity to thermal detection (i, m), cold (m) and heat pain (l), mechanical pain (i) and pressure pain thresholds (i, m). QST can be applied for non-invasive assessment of sensory nerve function (Ab-, A[delta]- and C-fiber) in the orofacial region and may be useful in the diagnosis of trigeminal nerve disorders in patients. Regional threshold differences may be due to different receptor trimming in hairy skin and oral mucosa.