Studies on artificial interferences in subjects with no temporomandibular (TMD) history have shown adaptation to the interference within a fairly short period of time. The role of occlusal factors in the etiology of TMD has therefore been questioned. The results might have been different, however, if subjects with a prior TMD history had been included in the study groups. To test this assumption in a randomized double-blind clinical set-up, we included healthy women without (n = 26) as well as with (n = 21) an earlier TMD history. Both groups were randomly divided into true and placebo interference groups. Artificial interferences were introduced in the true interference groups and simulated in the placebo groups. The subjects were followed for 2 weeks, after which the interferences were removed. The subjects without a TMD history showed fairly good adaptation to the interferences, but the subjects with a TMD history and true interferences showed a significant increase in clinical signs compared to the other groups. We suggest that the etiological role of occlusal interferences in TMD may not have been correctly addressed in previous studies with artificial interferences and allow no conclusions as regards TMD etiology.

In patients with otalgia, infectious otolaryngologic diseases should be ruled out. Then the patients without infection should be remitted to a dentist with stomatognathic experience. In the absence of temporomandibular disorders, further medical consultations (e.g., otorhinolaryngological, neurological, physiatric, and psychiatric) are indicated.

In a previous double-blind randomized controlled study, subjects with a history of temporomandibular disorder (TMD) reacted to artificial interference with more signs of TMD than did subjects with no TMD history. In the present study, we analysed the subjective reactions of these individuals on several symptom scales. Every day during the 2-week follow-up period, the subjects rated the intensity of their symptoms on 9 VAS scales (occlusal discomfort, chewing difficulties, tender teeth, fatigue in the jaws, headache, facial pain, opening difficulty, bruxism, ear symptoms). Subjects with a history of TMD and true interferences reported stronger symptoms than subjects with no TMD history and placebo interferences. The most prominent symptoms were occlusal discomfort and chewing difficulties. The difference in outcome between the groups with and without a TMD history suggests that there are individual differences in vulnerability to occlusal interferences. It is likely that the etiological role of occlusal interferences in TMD has not been correctly addressed in previous studies on artificial interferences.

No abstract

In clinical practice, it is commonly assumed that occlusal splints have therapeutic value in the treatment of temporomandibular disorders CTMD), but the evidence based on randomized controlled trials is scarce. This study evaluated the short-term (10-week) efficacy of a stabilization splint in subjects with recurrent secondary otalgia and active TMD treatment need using a randomized, controlled, double-blind design. Thirty-six subjects were randomly allocated to the two treatment groups: the stabilization splint and the control splint group. After 10 weeks' treatment, the intensity of secondary otalgia, measured on a VAS scale (from 0 to 100 mm), decreased statistically significantly in the stabilization splint group (t 2.12; P 0.006), but not in the control group. Improvement in active TMD treatment need in subjects showing moderate or severe signs and symptoms of TMD was reported significantly more often in the stabilization splint group than in the control splint group (chi2 5.71; P.017). A statistically significant decrease in the Helkimo clinical dysfunction index was seen in the subjects with stabilization splint (Z-2.63; P.009), but not in the subjects with control splint. The results indicate that the use of a stabilization splint is beneficial with regard to secondary otalgia and active TMD treatment need.