Tapio Jämsä

Occlusal adjustment and the incidence of demand for temporomandibular disorder treatment

STATEMENT OF PROBLEM Contrary to clinical opinion, the structural risk from dental occlusion in temporomandibular disorders has been questioned or considered to be insignificant in clinical practice. PURPOSE This study tested the effect of elimination of occlusal interference through occlusal adjustment, on the incidence of temporomandibular disorders. MATERIAL AND METHODS In a controlled clinical trial of 146 healthy children and adolescents, half of the subjects underwent occlusal adjustment aimed at elimination of the presumed structural risk, and the other half underwent mock adjustment. Adjustments were repeated every 6 months over a period of 4 years. The outcome variable was the incidence of temporomandibular disorders, operatively defined as request for treatment of symptoms characteristic of the disorders with presence of clinical signs demonstrated in the muscles of mastication and/or jaw joint. RESULTS The cumulative incidence rate was 9/67 in the mock adjustment group and 1/60 in the real adjustment group, for a relative risk of 8.06. The difference between groups was statistically significant (p = 0.019). CONCLUSIONS Elimination of the presumed structural risk from the dental occlusion appeared to significantly reduce the incidence of temporomandibular disorders in a select group of young subjects.

Effect of artificial occlusal interferences depends on previous experience of temporomandibular disorders

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.

Headache children with temporomandibular disorders have several types of pain and other symptoms.

The aim was to investigate the association between temporomandibular disorders (TMD) and overall muscle tenderness, depressive symptoms, sleep difficulties, headache frequency and related symptoms in children with primary headache in comparison with controls. Based on an unselected population sample of 1135 Finnish schoolchildren classified according to the type of headache at age 12, altogether 297 children aged 13-14 from different headache groups and healthy controls were randomly selected for an interview and clinical examinations. Children with migraine had more TMD signs than children with nonmigrainous headaches or healthy controls. High TMD total scores were associated with palpation tenderness in other parts of the body and with frequent headache attacks. We conclude that children with overall headache, migraine in particular, and high total TMD scores showed an increased overall tenderness to muscle palpation and multiply manifested hypersensitivity pain.

Subjective reactions to intervention with artificial interferences in subjects with and without a history of temporomandibular disorders.

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.

Signs and symptoms of temporomandibular disorders in children with different types of headache

Headache is a common symptom among children and teenagers. Both bruxism and muscle and joint tenderness have been found in children with headache. Children with migraine headache report more temporomandibular disorder (TMD)symptoms than do those with tension-type headache. The aim of the present study was to investigate the association of different types of headache with TMD and sex in children. Altogether 297 randomly selected schoolchildren aged 13–14 years participated in a blind study setting. There were no statistically significant differences between the headache groups with regard to TMD signs, although the migraine and migraine-type headache groups had the highest percentage of subjects with more severe TMD signs. Nor were there any statistical differences between sexes or between the headache groups with regard to subjective symptoms of TMD. The present results with children differed from earlier results with adults. First, no association was found between tension headache and TMD, and, second, no sex difference in TMD children was observed at this age.

Psychological factors and responses to artificial interferences in subjects with and without a history of temporomandibular disorders

Objective. It has often been suggested that psychological factors play a role in temporomandibular disorders (TMD). However, reports on psychological factors in TMD patients and controls have been equivocal. In a previous double-blind randomized controlled study, subjects with a TMD history showed more clinical signs and subjective symptoms and adapted less well to the artificial interferences than subjects without an earlier TMD history. In the present study, we analyzed the associations of psychological factors with symptom responses and adaptation to interferences. Material and Methods. Before the intervention, the subjects filled in questionnaires dealing with personality traits, level of psychological and somatic stress symptoms, coping strategies, and health beliefs. Every day during the 2-week follow-up period, the subjects rated the intensity of their symptoms on 9 modified visual analog scales (VAS). Results. Health hardiness, positive socialization history and inhibition of aggression were associated with weaker symptom responses and better adaptation to true artificial interferences. Some personality characteristics in subjects with an earlier TMD history tended to associate with higher symptom reporting despite the type of intervention. Conclusions. Psychological factors appeared significant for the symptom responses to artificial interferences, and they seem to play a different role in responses in subjects with an earlier TMD history compared to those without.

Health risk from occlusal interferences in females.

The purpose of the present study was to test the effect of elimination of occlusal interferences on the incidence of requests for treatment of symptoms in the head and cervicobrachial region. One hundred and twelve females 45 years of age or under, were randomly divided into a treatment group (n = 54) and a control group (n = 58). The former underwent occlusal adjustment and the latter grinding that did not affect occlusal contacts. The treatments were repeated every 12 months over a period of 4 years. The outcome variable was a spontaneous request for treatment. Statistical analyses included chi-square tests for categorical variables and a t- or Wilcoxon ranked sum test for continuous variables. Poisson regression was used to compare the risk of seeking treatment between the groups. The cumulative incidence rate of treatment requests was 2/54 in the treatment group and 11/58 in the control group. The relative risk was 5.12. The 95 per cent confidence limits were 1.14 and 23.1, respectively. The difference between groups was statistically significant (P = 0.0336). Systematic elimination of occlusal interferences significantly reduced the incidence of requests for treatment of symptoms in the head and cervicobrachial region. This is in contrast with the view that there is no, or at best, an insignificant health risk from occlusal interferences.

Prevention of temporomandibular disorder-related signs and symptoms in orthodontically treated adolescents: A 3–year follow-up of a prospective randomized trial

Recommendations about the need for occlusal adjustment after malocclusion therapy are inconclusive. A total of 123 orthodontically treated healthy adolescents (88 girls, 35 boys; 14.8 +/- 1.7 years old) agreed to participate in the present study. The subjects were interviewed and examined for signs and symptoms related to temporomandibular disorder (TMD) and were randomly allocated to intervention (n = 63) and control (n = 60) groups. At base line, occlusal adjustment was carried out for the intervention group and repeated every 6 months thereafter as needed. Mock adjustments were performed for the control group. At the end of the 3rd year 118 subjects (96%) turned up for re-examination. The number of subjects with palpatory pain of the masticatory muscles, and with occlusal centric slides decreased significantly in the intervention group but not in the control group (P < 0.001). In conclusion, occlusal adjustment therapy may prevent the occurrence of TMD signs in orthodontically treated healthy adolescents.

Are signs of temporomandibular disorders stable and predictable in adolescents with headache

The aim of the present study was to study changes in signs and symptoms of temporomandibular disorders (TMD) and factors predicting TMD signs in adolescents with and without headache. A population-based sample (n = 212) of 13-year-olds with and without headache was re-examined at the age of 16. The study included a questionnaire, face-to-face interview and somatic examination. In addition, a neurological examination, a muscle evaluation and a stomatognathic examination were performed. Significant changes were seen in TMD signs during the follow-up, but TMD signs at the end of the follow-up could not be predicted by baseline headache, sleeping difficulties, depression or muscle pain. TMD signs at the age of 16 were associated with female gender and muscle pain. We conclude that considerable changes in TMD signs occur in the follow-up of adolescents with and without headache. Headache-related TMD are not predictable in adolescents with and without headache.

Familial occurrence of signs of temporomandibular disorders in headache children and their mothers

Objective. Earlier studies have provided evidence of genetic inheritance of headache, especially migraine, but no familial occurrence has been found regarding temporomandibular disorders (TMD). In adults, headache and TMD have been found to be associated with each other, but studies on children are few. The aim of the present study was to test the hypothesis that there is no association between signs of TMD in 13-year-old headache children and their mothers. Material and methods. The study population was a nested case-control study of the population-based Finnish Family Competence Study originally consisting of over 1000 families. A structured questionnaire was sent to the families of 6-year-old children. A clinical examination was performed in 96 children with headache and 96 pairwise controls. At the age of 13 years, 75 of these same 96 children with headache and 79 of 96 headache-free controls participated in pediatric and stomatognathic examinations. Moreover, the mothers (n=154) filled in a structured headache questionnaire and participated in the stomatognathic examination. Results. No association between mothers and childs TMD signs was found. There was a significant association between signs of TMD and both migraine and tension-type headache in children. In mothers, the association was significant only between migraine and TMD signs. Conclusions. Familial occurrence of signs of TMD cannot be found in headache children and their mothers.