Aims: To test whether standardized palpation around the lateral pole of the condyle can influence mechanical sensitivity and unpleasantness and evoke referred sensations/pain in healthy individuals.
Methods: Palpometers (0.5, 1.0, and 2.0 kg) with spherical extensions were applied around the lateral pole of the condyle in relaxed and protruded positions of the mandible for 2, 5, and 10 s in 30 healthy participants. Mechanical sensitivity, unpleasantness, and referred sensations/pain were assessed using a 0 to 100 numeric rating scale (NRS) for each palpation. The NRS scores were compared using ANOVA and the McNemar test.
Results: Participants reported significantly higher mechanical sensitivity and unpleasantness scores for the 2.0-kg stimulus compared with the 0.5- and 1.0-kg stimuli for a duration of 2, 5, and 10 s (mean NRS > 50; p < 0.001). Application of a 1.0-kg stimulus was significantly different from the 0.5- and 2.0-kg stimuli applied for 5 s (mean NRS < 50; p < 0.001). One-third of participants reported referred sensations/pain.
Conclusion: Application of a 2.0-kg stimulus around the lateral pole of the condyle is painful and unpleasant regardless of the duration of palpation. Application of a 1.0-kg stimulus for 5 s was found to be nonpainful and not unpleasant in healthy participants. Thus, this study supports the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) recommendation for standardized examination of the temporomandibular joint and indicates that referred sensation/pain is a common finding in healthy individuals.