Muscle Pain Modulates Mastication: An Experimental Study in Humans

摘要: In this study, pain was induced in the masseter muscle by tonic infusion of hypertonic saline (5%) for up to 800 seconds 12 healthy men. Subjects continuously scored intensity on a 10-cm visual analogue scale. Mastication ipsilateral and contralateral side quantitatively assessed with use jaw-tracking electromyograph recordings jaw-closing muscles before, during, after periods constant intensity. The maximum voluntary occlusal force (MVOF) during short static contractions also monitored. Jaw movements electromyographic data were divided into single masticatory cycles analyzed cycle-by-cycle basis account intercycle variability. all subjects, caused deep localized at clinically relevant (mean VAS +/- SE, 4.6 .3 cm). MVOF significantly affected (P < .0005), lower compared prepain postpain .05). significant number cycles, averaged activity their agonist function decreased both painful mastication These changes are probably reflection natural bilateral recruitment pattern mastication. Significant jaw could not be detected present device, but further studies more accurate sensitive devices needed.