Effects of Experimental Tooth Clenching on Pain and Intramuscular Release of 5-HT and Glutamate in Patients With Myofascial TMD
2015 (English)In: The Clinical Journal of Pain, ISSN 0749-8047, E-ISSN 1536-5409, Vol. 31, no 8, 740-749 p.Article in journal (Refereed) Published
Objectives: It has been suggested that tooth clenching may be associated with local metabolic changes, and is a risk factor for myofascial temporomandibular disorders (M-TMD). This study investigated the effects of experimental tooth clenching on the levels of 5-HT, glutamate, pyruvate, and lactate, as well as on blood flow and pain intensity, in the masseter muscles of M-TMD patients. Methods: Fifteen patients with M-TMD and 15 pain-free controls participated. Intramuscular microdialysis was performed to collect 5-HT, glutamate, pyruvate, and lactate and to assess blood flow. Two hours after the insertion of a microdialysis catheter, participants performed a 20-minute repetitive tooth clenching task (50% of maximal voluntary contraction). Pain intensity was measured throughout. Results: A significant effect of group (P less than 0.01), but not of time, was observed on 5-HT levels and blood flow. No significant effects of time or group occurred on glutamate, pyruvate, or lactate levels. Time and group had significant main effects on pain intensity (P less than 0.05 and less than 0.001). No significant correlations were identified between: (1) 5-HT, glutamate, and pain intensity; or between (2) pyruvate, lactate, and blood flow. Discussion: This experimental tooth clenching model increased jaw muscle pain levels in M-TMD patients and evoked low levels of jaw muscle pain in controls. M-TMD patients had significantly higher levels of 5-HT than controls and significantly lower blood flow. These 2 factors may facilitate the release of other algesic substances that may cause pain.
Place, publisher, year, edition, pages
Lippincott, Williams andamp; Wilkins , 2015. Vol. 31, no 8, 740-749 p.
temporomandibular disorders; serotonin; glutamate; masseter muscle; bruxism; microdialysis
IdentifiersURN: urn:nbn:se:liu:diva-120641DOI: 10.1097/AJP.0000000000000154ISI: 000358207900009PubMedID: 25232860OAI: oai:DiVA.org:liu-120641DiVA: diva2:847596
Funding Agencies|Faculty of Odontology at Malmo "University, Malmo", Sweden; Swedish Dental Society; Swedish Rheumatism Association; Karolinska Institutet, Huddinge, Sweden; Swedish Research Counsil2015-08-202015-08-202016-04-25