Changes in headache after treatment of mandibular dysfunction

The Effect of Flat Dual-Cure Stabilizer Occlusal Splint in Pain Relief of Individuals Suffering from Migraine Headaches

Background:

No study on the effect of dual-cure stabilizer splint without canine ramp in migraine patients is present.

Objective:

This study was conducted to determine the effects of maxillary flat dual-cure stabilizer occlusal splint on severity, frequency and episodes of headaches in individuals suffering from a migraine.

Methods:

In this interventional clinical trial, 30 eligible patients were divided into 2 groups (case and control); each group consisted of 8 men and 7 women. Dual-cure stabilizer splint was made for patients in the case group and they used the adjusted splint 20 hours a day for 6 weeks. The severity, frequency and episodes of migraine attacks before and after using the splint were determined. For grading pain, severity visual analogue scale was used. The data were analyzed using SPSS 20 and Kolmogorov-Smirnov test and paired t-test.

Results:

The severity, frequency, and episodes of migraine attacks before and after using the splint were reduced by 56%, 68%, and 72%, respectively. The reduction was statistically significant (p < 0.05).

Discussion:

Despite the effect of occlusal devices on the migraine disorder is controversial, the most researchers agree that using these appliances can be effective in reducing headache in migraine patients.

Conclusion:

Given the favorable effects of dual-cure stabilizer splint on reducing the severity, frequency and episodes of migraine headaches, the device can be used as an effective alternative therapy besides common pain-relieving methods.

Temporomandibular Disorders and Headache

Temporomandibular disorders (TMD) and primary headaches can be perpetual and debilitating musculoskeletal and neurological disorders. The presence of both can affect up to one-sixth of the population at any one time. Initially, TMDs were thought to be predominantly musculoskeletal disorders, and migraine was thought to be solely a cerebrovascular disorder. The further understanding of their pathophysiology has helped to clarify their clinical presentation. This article focuses on the role of the trigeminal system in associating TMD and migraine. By discussing recent descriptions of prevalence, diagnosis, and treatment of headache and TMD, we will further elucidate this relationship.

The effect of disocclusion time-reduction therapy to treat chronic myofascial pain: A single group interventional study with 3 year follow-up of 100 cases

PURPOSE

The purpose of this study is to evaluate the longevity of reduced disclusion time in treating and removing myofascial pain dysfunction symptoms following the T-Scan-based, immediate complete anterior guidance development (ICAGD) coronoplasty. This measured occlusal adjustment has been shown to reduce the muscle hyperactivity of myofascial pain.

METHODS

Myofascial pain symptomatic patients were recruited as per the diagnostic criteria for temporomandibular disorders (TMDs), including the clinical protocol and assessment instruments outlined by the international RDC/TMD consortium network (version: January 20, 2014) to assess the efficacy of reduced disclusion time in left and right lateral excursions to resolve the myofascial pain symptoms. As per the inclusion and exclusion criteria, 100 cases were treated with ICAGD in three visits, each 1 week apart. Recall disclusion time measurements were recorded every 3 months over 3 years. The RDC/TMD questionnaire was used for symptom assessment at every recall visit. ICAGD brought pretreatment prolonged disclusion time down to <0.4 s, as quantified from T-Scan force and time data records, while the subjects were assessed for symptom relief. The Wilcoxon signed-rank test was used for statistical analysis (P < 0.05).

RESULTS

Changes in the intensity of many symptoms from reducing the disclusion time to <0.4 s were statistically significant from treatment day 1, and onward through the 3-year period of observation (P < 0.05).

CONCLUSION

The results indicate that ICAGD reduces the musculoskeletal symptoms of myofascial pain, such that this methodology increases clinical therapeutic success.

The effect of reduced disclusion time in the treatment of myofascial pain dysfunction syndrome using immediate complete anterior guidance development protocol monitored by digital analysis of occlusion

STATEMENT OF PROBLEM

Chronic myofascial pain dysfunction syndrome (MPDS) has been a nightmare for patients suffering from it, who have been treated with various treatment options with varied outcomes. This population of patients has been neglected, due to nagging revisits to a clinician and decreased percentage of success.

OBJECTIVE

T-Scan-based immediate complete anterior guidance development (ICAGD) has been shown by a researcher to reduce the muscle hyperactivity consistent with MPDS. The purpose of this study is to evaluate the effect of reduced disclusion time in lateral excursions in treating the MPDS symptoms.

MATERIALS AND METHODS

Fifty-one myofascial pain patients with symptoms in the area of the head and neck region were treated with ICAGD. The quantified force and time data from T-Scan records were used to correct the prolonged disclusion time, and the subjects were assessed for the symptom relief. The Wilcoxon Signed Ranks Test was used for statistical analysis (P<0·05 denotes significant changes).

RESULTS

The changes in disclusion time and intensity of various symptoms were found to be statistically significant (P<0·05) from Day 1 onwards, and patients were relieved of their symptoms after reduction of disclusion time of less than 0·5 seconds.

CONCLUSION

The results clearly indicated that ICAGD protocol reduces musculoskeletal-based symptoms of MPDS patients, and this protocol can prove beneficial for the clinical treatment success.

Occlusal adjustment using the bite plate-induced occlusal position as a reference position for temporomandibular disorders: a pilot study

Background

Many researchers have not accepted the use of occlusal treatments for temporomandibular disorders (TMDs). However, a recent report described a discrepancy between the habitual occlusal position (HOP) and the bite plate-induced occlusal position (BPOP) and discussed the relation of this discrepancy to TMD. Therefore, the treatment outcome of evidence-based occlusal adjustments using the bite plate-induced occlusal position (BPOP) as a muscular reference position should be evaluated in patients with TMD.

Methods

The BPOP was defined as the position at which a patient voluntarily closed his or her mouth while sitting in an upright posture after wearing an anterior flat bite plate for 5 minutes and then removing the plate. Twenty-one patients with TMDs underwent occlusal adjustment using the BPOP. The occlusal adjustments were continued until bilateral occlusal contacts were obtained in the BPOP. The treatment outcomes were evaluated using the subjective dysfunction index (SDI) and the Helkimo Clinical Dysfunction Index (CDI) before and after the occlusal adjustments; the changes in these two indices between the first examination and a one-year follow-up examination were then analyzed. In addition, the difference between the HOP and the BPOP was three-dimensionally measured before and after the treatment.

Results

The percentage of symptom-free patients after treatment was 86% according to the SDI and 76% according to the CDI. The changes in the two indices after treatment were significant (p < 0.001). The changes in the mean HOP-BPOP differences on the x-axis (mediolateral) and the y-axis (anteroposterior) were significant (p < 0.05), whereas the change on the z-axis (superoinferior) was not significant (p > 0.1).

Conclusion

Although the results of the present study should be confirmed in other studies, a randomized clinical trial examining occlusal adjustments using the BPOP as a reference position appears to be warranted.

Are headache and temporomandibular disorders related? A blinded study

To investigate overlaps between headache and temporomandibular disorders (TMD) in a clinical headache population and to describe the prevalence of TMD in headache patients, 99 patients referred to a specialized headache centre were diagnosed according to Research Diagnostic Criteria for TMD (RDC/TMD) and classified in headache groups according to the International Classification of Headache Disorders, second edition for headache diagnoses in a blinded design. The prevalence of TMD in the headache population was 56.1%. Psychosocial dysfunction caused by TMD pain was observed in 40.4%. No significant differences in TMD prevalence were revealed between headache groups, although TMD prevalence tended to be higher in patients with combined migraine and tension-type headache. Moderate to severe depression was experienced by 54.5% of patients. Patients with coexistent TMD had a significantly higher prevalence of depression-most markedly in patients with combined migraine and tension-type headache. Our studies indicate that a high proportion of headache patients have significant disability because of ongoing chronic TMD pain. The trend to a higher prevalence of TMD in patients with combined migraine and tension-type headache suggests that this could be a risk factor for TMD development. A need for screening procedures and treatment strategies concerning depression in headache patients with coexistent TMD is underlined by the overrepresentation of depression in this group. Our findings emphasize the importance of examination of the masticatory system in headache sufferers and underline the necessity of a multidimensional approach in chronic headache patients.

Tension-type headache: current research and clinical management

Tension-type headache (TTH) is the most common form of headache, and chronic tension-type headache (CTTH) is one of the most neglected and difficult types of headache to treat. The pathogenesis of TTH is multifactorial and varies between forms and individuals. Peripheral mechanisms (myofascial nociception) and central mechanisms (sensitisation and inadequate endogenous pain control) are intermingled: the former predominate in infrequent and frequent TTH, whereas the latter predominate in CTTH. Acute therapy is effective for episodes of TTH, whereas preventive treatment--which is indicated for frequent and chronic TTH--is, on average, not effective. For most patients with CTTH, the combination of drug therapies and non-drug therapies (such as relaxation and stress management techniques or physical therapies) is recommended. There is clearly an urgent need to improve the management of patients who are disabled by headache. This Review summarises the present knowledge on TTH and discusses some of its more problematic features.

Temporomandibular disorders and other causes of facial pain

Temporomandibular disorders and facial pain cause significant discomfort and disability for affected patients. Understanding the clinical presentation, pathogenesis, and therapy is essential in helping patients who have these problems. This article critically reviews these aspects, with an emphasis on their relationship to headache.

Temporomandibular disorders and headache

Headache is a common symptom, but when severe, it may be extremely disabling. It is assumed that patients who present to dentists with headache often are diagnosed with a temporomandibular disorder (TMD), although many may have migraine. TMD as a collective term may include several clinical entities, including myogenous and arthrogenous components. Because headache and TMD are so common they may be integrated or separate entities. Nevertheless, the temporomandibular joint (TMJ) and associated orofacial structures should be considered as triggering or perpetuating factors for migraine. This article discusses the relationship between the TMJ, muscles, or other orofacial structures and headache.

Treatment outcome of short- and long-term appliance therapy in patients with TMD of myogenous origin and tension-type headache

The aim was to compare the short- and long-term effect of a stabilization appliance with a control appliance in myofascial pain patients suffering from episodic or chronic tension-type headache. Sixty patients (mean age 29 +/- 12 years) with temporomandibular disorders (TMD) of myogenous origin and headache were studied in this prospective controlled study. Seventy-seven per cent of the patients reported episodic and 23% chronic tension-type headache at the start of the study. The 60 patients were randomly assigned to a treatment group (stabilization appliance) or to a control group (control appliance). The patients were interviewed regarding symptoms of headache and myofascial pain and clinically examined for masticatory muscle tenderness. At the 10-week and the 6- and 12-month evaluations of appliance therapy, the treatment outcome of tension-type headache was studied. At the 10-week evaluation, 17 patients dropped-out from the control group by requesting another appliance and receiving a stabilization appliance. Another patient in the control group dropped out later during the trial. In an intent-to-treat analysis, significant differences in improvement of headache between treatment and control groups were found at the follow-ups. A 30% reduction of muscles tender to palpation correlated significantly to improvement of headache at all follow-ups. The stabilization appliance seems to have a positive effect on tension-type headache, both in a short- and in a long-term perspective in patients with TMD with pain of myogenous origin.

Headache improvement through TMD stabilization appliance and self-management therapies

The purpose of this study was to assess headache response of unselected neurology clinic chronic headache patients to TMD stabilization appliance and self-management therapies, and to identify features of patients whose headaches are more likely to improve from these therapies. Twenty chronic headache patients in a nontreatment control period were provided appliance and self-management therapies, evaluated five weeks after therapy, and those who chose to continue using their appliances were evaluated three months later. The mean pretreatment Headache Disability Inventory (HDI) score of 64.5 suggested the headaches were severe. After five weeks, the mean HDI score decreased by 17 percent (p<0.003), headache medication consumption dropped by 18 percent (p<0.0001), and headache symptoms decreased by 19 percent (p<0.002). Comparing the three months with pretreatment follow-up, the fourteen participants who chose to continue using their appliances had a mean HDI score decrease of 23 percent (p<0.003), headache medication consumption drop of 46 percent (p<0.001), and headache symptom decrease of 39 percent (p<0.001). There was no correlation between response and headache type (p=0.722). These results suggest appliance and self-management therapies can be beneficial for many severe headache patients, irrespective of the headache type (tension-type, migraine without aura, and migraine with aura).

[Muscular-arthroscopic pain: often unappreciated]

Myoarthropathic pain, most often due to masticatory myalgia, is the major source of orofacial pain. Its diagnosis is not always easy because the diagnostic signs are not pathognomonic and they may occur also with other pain disorders. The pain intensity fluctuates, and mild to medium intensity pain has the tendency to subside spontaneously or can be alleviated with simple, non-invasive therapies such as counseling, self-control, analgesics, physiotherapy, and occlusal appliances. For most patients a combination of counseling, self-control and physiotherapy (home program) is sufficient to relieve the pain. Occlusal appliances should, therefore, be used only if these modalities fail or if pain is present on awakening. Only in a small percentage of patients the myoarthropathic pain persists and becomes chronic. The factors that determine pain chronicity are complex and most likely due to the interaction of biomedical factors - such as the persistence of peripheral nociceptive input, neuroplastic changes at spinal and supraspinal levels (cortical reorganisation)- with psychosocial factors, in addition, possibly, to a polymorphism of the catechol-o-methyltransferase gene. Patients with chronic myogenic pain need a multimodal therapy, according to the biopsychosocial pain model. In addition to the modalities just described, the treatment must address also the affective, emotional, cognitive and behavioural pain component and be tailored to the single patient based on his/her psychosocial and constitutional characteristics. The goal is not pain relief but improvement of the quality of life by teaching the patient more efficient pain coping strategies by means of behavioural and relaxation techniques. In addition, tricyclic antidepressants may be used in order to treat the somatic pain component caused by the neuroplastic changes that take place in the central nervous system in chronic pain conditions.

Occlusion: Reflections on science and clinical reality

The last 50 years have seen progress in emphasizing scientific evidence as a basis for dental practice, including occlusal therapy. Although a proper understanding of the contributory role of occlusion to temporomandibular disorders should not be minimized, the importance of occlusion in other areas of dental education and practice should not be overlooked. The primary objective of this article is to discuss the nature of this problem as it relates to the duality of science and clinical reality in the evidence-based paradigm, information transfer, quality of evidence, clinical trials, and clinical aspects of occlusion. Some suggested solutions for the problem and thoughts on past and future perspectives of occlusion are expressed in context of inquiry.

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.

Overview of tension-type headache

Tension-type headache (TTH) is the most prevalent form of headache. Although it is not the most severe form of headache, it has a significant impact on society. In spite of this, little is known about its pathophysiology. Current International Headache Society classification has been called into question, and new classification approaches have been suggested. With reference to chronic TTH, the issue of analgesic rebound may confound the diagnosis. Transformed migraine and new persistent daily headaches are clarified and differentiated from chronic TTHs (CTTHs). The best documented abnormality found in TTHs is the presence of pericranial tenderness. It is generally believed that pain is initiated by a peripheral mechanism, most likely increased input from the myofascial nociceptors. In CTTH, there may be an impaired supraspinal modulation of the incoming stimuli. Whether there is an overlap in the continuum between TTH and migraine is controversial. Abortive and prophylactic treatments are discussed and wellness and adjunct therapy are also emphasized. Lastly, special attention is paid to the doctor-patient relationship in patients with difficult headaches.

An evidence-based assessment of occlusal adjustment as a treatment for temporomandibular disorders

STATEMENT OF PROBLEM

Occlusal adjustment therapy has been advocated as a treatment modality for temporomandibular disorders. In contrast to this position, a panel at the 1996 National Institute of Health technology assessment conference on TMD indicated that no clinical trials demonstrate that occlusal adjustment is superior to noninvasive therapies.

PURPOSE

This article summarizes the published experimental studies on occlusal adjustments and temporomandibular disorders.

MATERIAL AND METHODS

Eleven research experiments involving 413 subjects with either bruxism (n = 59), temporomandibular disorders (n = 219), headaches and temporomandibular disorders (n = 91), or chronic cervical pain (n = 40) were selected for critical review from the English dental literature.

RESULTS

Three experiments evaluated the relationship between occlusal adjustment and bruxism. Six experiments evaluated occlusal adjustment therapy as a treatment for patients with primary temporomandibular disorders. One experiment looked at occlusal adjustment effect on headache/temporomandibular disorder symptoms; another looked at its effect on chronic neck pain. Most of these experiments used a mock adjustment or a comparison treatment as the control condition in adults who had an existing nonacute general temporomandibular disorder. Overall, the data from these experiments did not demonstrate elevated therapeutic efficacy for occlusal adjustment over the control or the contrasting therapy.

CONCLUSION

The experimental evidence reviewed was neither convincing nor powerful enough to support the performance of occlusal therapy as a general method for treating a nonacute temporomandibular disorder, bruxism, or headache.

Occlusion and splint therapy

Control of occlusal contacts is important to the success of restorative dentistry. Tooth surface loss can contribute to a loss of stability in the occlusion. An occlusal splint is often part of pre-restorative management and can also have a valuable role in protecting both teeth and restorations from excessive loads and further wear.

The role of occlusal adjustment in the management of temporomandibular disorders

The use of occlusal adjustment as a treatment for temporomandibular disorders has been questioned because of lack of evidence that occlusal factors play an etiologic role; lack of evidence that this irreversible treatment modality has sufficient efficacy, when reversible modalities are available; the self-limiting character of the disorders; and the possibility of adverse effects. However, controlled clinical trials have yielded results that are difficult to explain unless occlusal factors have a causal role in temporomandibular disorders. Controlled clinical trials also suggest an effect for occlusal adjustment on chronic headaches and on chronic neck and shoulder pain in comparison with conventional treatments. Moreover, no adverse effects of properly conducted occlusal adjustments have been reported. In view of the possibility that occlusal factors have a causal role in temporomandibular disorders, research efforts on the role of occlusion should be intensified, and teaching should be revised accordingly.

A comparison of ICAGD (immediate complete anterior guidance development) to mock ICAGD for symptom reductions in chronic myofascial pain dysfunction patients

The purpose of this study is to assess what impact shortening disclusion time to less than .5 seconds during right and left mandibular excursions has on myofascial pain(s) symptoms present in a dental student population. Twenty-five dental students, who exhibited symptomatology consistent with myofascial pains patient, were divided into a treatment, control, and an untreated group. They participated in an occlusal adjustment study which measured changes in disclusion time, as well as, myofascial pains muscular symptom remissions resultant from treatment. The treated group of ten subjects received ICAGD occlusal adjustments to shorten their disclusion time to less than .5 seconds per mandibular excursion. The goal of this therapy was to totally disclude the posterior teeth in a measurable time frame of .5 seconds or less. The control group of eight subjects received mock ICAGD with tooth polishing. The goal of this therapy was to simulate ICAGD adjustments for possible placebo effect on symptom remissions. The untreated group had their disclusion times measured but received no treatment to adjust, or to simulate adjustment to their occlusion. The goal of analyzing an untreated group was to attempt to show that mock treatment (performed on the control subjects), or no treatment (performed on the untreated subjects), resulted in no measurable change in the disclusion time in either of these two subject groups. Each subject was recalled for disclusion time measurement four to five times in a one-year period of observation, at which time, they were required to report their myofascial pains symptom status by answering an ordinal scale questionnaire. The results suggest that shortening disclusion time to less than .5 seconds per mandibular excursion can induce remissions of many muscular myofascial pains symptoms. Additionally, mock ICAGD occlusal adjustments did not appear to be a factor in the control subjects treatment response, as this group showed no statistically significant symptom remissions.

Occlusal adjustment in patients with craniomandibular disorders including headaches. A 3- and 6-month follow-up

The aim of this study was to evaluate the therapeutic effect of occlusal adjustment on symptoms and signs of craniomandibular disorders (CMD), including headaches, after 3 and 6 months. Fifty patients were selected and randomly assigned to a treatment (T) or a control (C) group. All patients in the treatment group were subjected to occlusal adjustment, whereas the controls were comforted only. Pre- and post-treatment assessment of subjective symptoms and clinical signs was made by a dentist not performing the occlusal adjustment. There was significant improvement in overall subjective symptoms within the T group at the 3- and 6-month follow-up visits, but a statistically significant difference between groups was found at the 3-month follow-up only. With regard to changes in frequency of facial pain a significant deterioration was reported within the C group, which resulted in a significant difference between groups at the 6-month follow-up. No other significant differences were found within or between groups at the follow-ups with regard to the variables investigated. In conclusion, the results from this study that occlusal adjustment is a treatment modality with a statistically significant short-term effect on symptoms of CMD of muscular origin and superior to counseling.

Prevalence of craniomandibular disorders in adults of Ilala District, Dar-es-Salaam, Tanzania

The prevalence and distribution of signs and symptoms of craniomandibular disorders (CMD) were studied in a random sample of 100 adult Tanzanians. The associations between subjective and objective findings were analysed. Signs and symptoms of CMD were assessed by interview and clinical examination. Twenty-six per cent of subjects reported at least one symptom, and in 40% at least one clinical sign was present. No significant differences were observed between the sexes. Tenderness of the lateral pterygoid area and crepitation of the temporomandibular joint increased significantly with age. Several significant associations between subjective and objective findings were observed. The distribution of the signs and symptoms of CMD in Tanzanians was not dissimilar to that observed in the developed countries. The prevalence was not high by comparison, but sufficient to lend credence to the general view that CMD is a universal problem.

Occlusal abnormalities, pericranial muscle and joint tenderness and tooth wear in a group of migraine patients

Seventy-two migraine sufferers, whose attacks normally begin during or soon after waking from sleep, were compared with 37 age- and sex-matched controls to establish whether signs of mandibular dysfunction, occlusal discrepancies and known clenching or grinding habits were any more frequent among the former group. Temporomandibular joint tenderness or pain history, masticatory muscle tenderness and known clenching or grinding habits were found to occur at significantly increased levels in the migraine sufferers, with two-thirds of these patients reporting a parafunctional habit. Occlusal abnormalities, including non-working side or protrusive interferences and slides of greater than 1 mm to the intercuspal position, were found to occur at similar frequencies in the two groups. Assessment of wear of the occlusal surfaces also showed no difference, suggesting that any nocturnal habit with a role in migraine is more likely to be clenching in nature. In conclusion, evidence was found to support an aetiological role for nocturnal tooth clenching or grinding in migraine characterized by attacks that start predominantly during sleep or soon after waking, but no evidence of a link with occlusal factors was found in these patients.

Short-term effect of occlusal adjustment on craniomandibular disorders including headaches

The aim of this study was to assess the short-term effect of occlusal adjustment on craniomandibular disorders. Fifty patients were randomly selected and divided into a treatment (T) and a control (C) group. The initial clinical examination and the follow-up were made by one observer and the occlusal adjustment by another. There were no significant differences between groups with regard to frequency of headaches, facial pain, pain on mandibular function, or duration of headaches and facial pain. Fifty-two percent of the patients in the treatment group and 20% of the patients in the control group reported reduced subjective symptoms overall at follow-up examination. The improvement was statistically significant within the T group and significantly greater than in the C group. There was no significant change within or between groups with regard to frequency of headaches, facial pain, or pain on mandibular movements. There was an almost significant difference between groups after treatment with regard to changes in the number of tender muscles. The results of this study indicate that occlusal adjustment provides a general subjective improvement of craniomandibular disorders.

Soft occlusal splint therapy in the treatment of migraine and other headaches

Fifty-seven patients suffering from migraine, tension headache or tension vascular headache were prescribed a soft occlusal splint for night-time wear. Dental, psychosocial/psychiatric and neurological data were recorded prior to commencement of therapy and at the conclusion of a 3 month treatment period. A statistically significant number of patients presenting with migraine or tension vascular headache experienced marked improvement or complete relief of headache symptoms, but most patients suffering from tension headache failed to benefit from splint therapy. A majority of patients displaying intercurrent features of craniomandibular dysfunction experienced reduction in these symptoms also. There was a statistically significant association between TMJ improvement and headache type. Prior to treatment, patients who subsequently benefited from splint therapy in terms of headache improvement had experienced significantly fewer headaches than patients who failed to respond, although headache intensity and duration were similar in both groups. It is suggested that headache type and frequency may be prognostic indicators of the likely success of dental splint therapy in treatment of headache. Nevertheless, the use of occlusal splints in the treatment of patients complaining of headache in the absence of evidence of craniomandibular dysfunction should not be embarked upon until medical examination has excluded the possibility of organic neurological disorder.

Assessment of occlusal interferences

The variability in the assessment of occlusal variables was investigated in eight subjects by the repeated registrations of four observers. The following variables were investigated in three different ways: sliding between the RCP (retruded contact position) and the ICP (inter-cuspal contact position) in the sagittal, vertical and lateral plane. Interferences during lateral movements on the working and balancing sides as well as interferences causing deviation of the mandible during protrusive movements were recorded. The intra- and inter-observer error for the measurement of sagittal and vertical distance RCP-ICP was within acceptable limits. There was no significant difference between the three methods used. The intra- and inter-observer agreement between duplicate recordings of the lateral distance RCP-ICP was high and there were no differences between the different measurement modalities. The inter-observer agreement was lower than the intra-observer agreement concerning presence/absence of balancing side interferences, and positive inter-observer agreement was only found on lateral movement more than 3 mm from the RCP or the ICP. The observer error for the variable working side interferences should be acceptable for future research, while the observer error for measurement of lateral deviation of the mandible upon protrusion was somewhat larger.

Association of functional state of stomatognathic system with mobility of cervical spine and neck muscle tenderness

Clinical signs of craniomandibular disorder, the mobility of the cervical spine, and neck-shoulder muscle tenderness were assessed or measured in a nonpatient sample of 57 and a patient sample of 76 subjects. Examinations performed after a 1-year interval showed that the frequency of signs of craniomandibular disorder had remained virtually unchanged. The functional state of the stomatognathic system was significantly associated with both mobility of the cervical spine and neck-shoulder muscle tenderness.

Response to occlusal treatment in headache patients previously treated by mock occlusal adjustment

Headache patients who had received mock occlusal adjustment and who, after the placebo treatment, were judged to have moderate to severe mandibular dysfunction were offered further treatment. The present study reports the results of occlusal treatment in 19 patients who were willing to undergo further treatment. Statistically significant reduction after occlusal treatment (occlusal adjustment, aided in some cases by temporary use of occlusal splints) was observed in clinical signs (P less than 0.05) and subjective symptoms (P less than 0.01) of mandibular dysfunction and in the frequency of headache (P less than 0.05). The results are complementary to our earlier clinical studies and corroborate the conclusion that improvements after occlusal treatment exceed those after placebo treatment.

Headache and dysfunction of the masticatory system in adolescents

An epidemiologic group of 285 17-year-old adolescents was studied with the aid of a questionnaire for frequency and intensity of headache and for symptoms of dysfunction of the masticatory system. They were also subjected to a functional examination of the masticatory system. Recurrent headaches occurred significantly more often among the girls (18%) than the boys (6%). Girls also reported significantly more intense headaches than boys. Fatigue in the jaws and difficulties in chewing were commoner in those with frequent and more intensive headaches. Tenderness to palpation of the masticatory muscles and impaired mandibular mobility were significantly commoner findings among those with recurrent headaches and those with more intense headaches. Tooth-grinding and clenching were related to frequency but not to intensity of headache. The investigation showed a significant relationship between frequency and intensity of headaches and signs and symptoms of dysfunction of the masticatory system.

Effect of occlusal adjustment on mandibular dysfunction. A double-blind study

A group of headache patients who also had many signs and symptoms of mandibular dysfunction were randomly assigned to treatment and placebo groups. All 48 patients in the treatment group received occlusal adjustment and 19 of them also splint therapy. In the placebo group all 43 patients received mock adjustment. The changes in symptoms and signs of mandibular dysfunction were evaluated after 8 months in the treatment group and after 4 months in the placebo group, in a double-blind design. Placebo treatment and real treatment were equally effective in relieving symptoms of mandibular dysfunction, but there was significantly more reduction in signs of dysfunction in the treatment group than in the placebo group. When tested statistically, this reduction appeared to be independent of the use of splints as an aid to treatment. It can be concluded that the elimination of occlusal disturbances was an effective treatment for mandibular dysfunction.