Orofacial pain of muscular origin is not associated with herpes virus-6 infection: a pilot study.

AIMS: To carry out a pilot study to test the hypothesis that human herpes virus-6 (HHV-6) infection or reactivation plays a role in the pathogenesis of temporomandibular disorders (TMD) of muscular origin (ie, localized myalgia). METHODS: Sixteen patients with localized myalgia participated in this pilot study. Thirty-six healthy individuals served as controls. The participants were examined clinically for the presence of the TMD according to the Research Diagnostic Criteria for TMD, and the salivary levels of HHV-6 were measured by quantitative polymerase chain reaction (qPCR). The Z test, Student t test, and Mann- Whitney U test were used as appropriate. RESULTS: The results demonstrated that 77.8% of healthy individuals were HHV-6 positive, but a significantly lower proportion (43.8%) of the TMD patients with localized myalgia were positive for HHV-6 (P < .05, Fisher exact test). The levels of HHV-6B DNA were lower in the saliva of HHV-6-positive TMD patients with localized myalgia (median: 564 genome/mL; range: 184 to 5,835 genome/mL) than in that of healthy individuals (median: 1,081 genome/mL; range: 193 to 8,807 genome/mL), but the difference was not statistically significant (P > .05, Mann-Whitney U test). CONCLUSION: The results of this pilot study indicate that HHV-6 infection or reactivation does not appear to play a role in the pathogenesis of TMD reflecting a localized myalgia.

Asymptomatic shedding of HSV-1 in patients undergoing oral surgical procedures and attending for noninvasive treatment.

Oral surgery and stress can trigger and/or increase asymptomatic shedding of herpes simplex virus type-1 (HSV-1) into human saliva. In this investigation we examined the frequency of HSV-1 shedding in 32 patients undergoing an oral surgery procedure compared with 40 control patients attending for noninvasive treatment. Control patients comprised 18 migraine patients and 22 patients with temporomandibular (TMD) joint problems. Nested-PCR was carried out on oral rinses collected from each patient prior to treatment and 7 days post-treatment. Fifty-two of sixty-one seropositive patients were positive for HSV-1 DNA in one or both oral rinses. The frequencies of HSV-1 shedding for the oral surgery and control patients were 84.6% and 85.7% respectively. Seropositive patients who started shedding after treatment were significantly higher in oral surgery patients (46.2%) compared to control patients (34.3%). Shedding of HSV-1 in the oral cavity is not only increased by direct surgical trauma, but also appears to be common in migraine and TMD patients attending for general dental treatment. Thus pain or pain-induced stress as well as anxiety associated with dental treatment may also be a risk factor for asymptomatic shedding in specific seropositive patients attending for dental treatment.