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Updated: Jun 3, 2026
Meal Duration as a Measure of Orofacial Nociceptive Responses in Rodents
Published on: January 10, 2014
Effect of experimental chewing on masticatory muscle pain onset
Paulo César Rodrigues Conti1, Rafael dos Santos Silva, Carlos dos Reis Pereira de Araujo
1Department of Prosthodontics, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil. pcconti@fob.usp.br
Objectives:
To evaluate the effect of a chewing exercise on pain intensity and pressure-pain threshold in patients with myofascial pain.
Methods:
Twenty-nine consecutive women diagnosed with myofascial pain (MFP) according to the Research Diagnostic Criteria comprised the experimental group and 15 healthy age-matched female were used as controls. Subjects were asked to chew a gum stick for 9 min and to stay at rest for another 9 min afterwards. Pain intensity was rated on a visual analog scale (VAS) every 3 min. At 0, 9 and 18 min, the pressure-pain threshold (PPT) was measured bilaterally on the masseter and the anterior, medium, and posterior temporalis muscles.
Results:
Patients with myofascial pain reported increase (76%) and no change (24%) on the pain intensity measured with the VAS. A reduction of the PPT at all muscular sites after the exercise and a non-significant recovery after rest were also observed.
Conclusion:
The following conclusions can be drawn: 1. there are at least two subtypes of patients with myofascial pain that respond differently to experimental chewing; 2. the chewing protocol had an adequate discriminative ability in distinguishing patients with myofascial pain from healthy controls.
