Aim: To evaluate the impact of localized and widespread pain on the outcome of oral appliance treatment of headache frequency and intensity in patients with temporomandibular disorders (TMD).
Materials and methods: The present multicenter study comprised 65 myofascial TMD patients diagnosed according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Pain site drawings were completed at baseline. All patients received oral appliance treatment. Treatment outcome was followed up and analyzed (chi-square test, Mann-Whitney U test, Wilcoxon signed-rank test) for two pain profiles, being localized pain (face and head, n = 26) and widespread pain (pain sites also outside face and head, n = 39) at 6 and 10 weeks, and 6 and 12 months.
Results: At baseline, there were no differences in frequency of headache between the pain profile groups. Headache frequency decreased significantly within both groups (localized pain P = 0.008, widespread pain P < 0.001) during follow-up, with no differences between the groups. The intensity of headache differed significantly between the groups at baseline (P = 0.002). During follow-up, the decrease of headache intensity was statistically significant within both groups (localized pain P = 0.007, widespread pain P < 0.001), with no difference shown between groups at 6 weeks and 12 months. At the 6-week follow-up, 52% of all patients showed a 30% reduction of headache intensity; at the 12-month follow up, a 30% reduction was observed in 54% of the patients.
Conclusion: The present study indicates that oral appliance treatment has a similar positive effect on headache frequency and intensity, regardless of whether the myofascial TMD pain is localized or widespread.