This case report illustrates the interrelationship between temporomandibular disorders (TMD) and headache. It highlights the important role of the dentist in the management of individuals suffering from recurrent headache. It also emphasizes that clinician's prescription for TMD therapy should be scientifically and conservatively based. 

 
Chronic headache is an almost universal finding with a reported prevalence of the order of 20% in most communities.¹ In the United States, it has been estimated that 5-10% of the population seek treatment for severe headache.² Thus, the esti- mated socio-economic costs due to the number of patients suffering from headache and accompany- ing lost man-hours are enormous. Signs and symptoms of temporomandibular disorders (TMD) are common in most populations.³ A strong relationship between TMD and headache has been reported.⁴ It is mainly the tension-type of headache that is related to the presence of dysfunction of the masticatory system, although the "common mig- raine" type may also be associated. Various treat- ment strategies are applied for TMD and the clini- cian should remain aware that some of the more commonly prescribed therapies lack scientific val- idity.⁵
 

Medical History

In November 1991, a 45-year-old Saudi female attended the College of Dentistry, King Saud University, with a 10-year history of severe continuous headache and tinnitus. She had previously been seen in the ENT Department at the King Khalid Uni- versity Hospital, where a clinical examination including a cephalogram had been performed. However, no significant findings were reported. In addition, she had been seen in the Department of Oral Medicine, College of Dentistry, but the examination, which included both orthopantomogram and tomograms of the temporomandibular joints (TMJ's), failed to reveal any abnormality of the jaws or the TMJ's. Treatment was nevertheless initiated by prescribing an analgesic/anti-inflammatory drug for one week. As this did not relieve the patients symptoms, she was referred to the Graduate TMJ Clinic.

Apart from complaints of headache on the right side, clicking of the TMJ, and tinnitus, no other significant findings were reported in the medical history. The patient considered her headache to be severe, and she had to take analgesics on a daily basis. There were no significant findings in the social history.

Clinical examination

The patient had a partially edentulous dentition with bilateral loss of the mandibular posterior teeth. Temporalis and lateral pterygoid muscles were ten- der to palpation, clicking of the right TMJ was pre- sent, and the mandibular anterior teeth exhibited moderate attrition. Ranges and patterns of mandibular movements were normal. There were neither occlusal interferences in or around the retruded contact position, and nor any working or non-working side interferences. Generally, the patients oral hygiene was good, and the caries and the periodontal status were equally good.

Diagnosis and treatment

Findings in the medical history and clinical examination justified a tentative diagnosis of headache due to temporomandibular disorder with neuromuscular background, with common "tension headache" as a differential possibility. The treatment plan consisted of:

1. Counselling about the relative harmlessness of the condition and its good prognosis.
2. Construction of a full coverage hard acrylic occlusal splint for the mandibular arch with a bilateral tissue-supported posterior extension [Figs. 1a, b, c and 2]
3. Follow-up after 2 weeks, 8 weeks, 6 months and 1 year.
4. Construction of a mandibular removable partial denture.

At 2-week follow-up, the patient reported that the splint was comfortable. She had used the occlusal splint every night, with some daytime use as well. The frequency of headache was slightly decreased, but the number of masticatory muscles tender to palpation was not reduced. At the 8-week follow-up the patients condition had substantially improved, both subjectively and clinically. The latter was evaluated by the reduction in number of muscle sites tender to palpation.

At the 6-month reassessment visit, the patient appeared visibly pleased with the treatment out- come. Her experience of headache was reduced to almost nil. Her tinnitus had also subsided. She was no longer having to take analgesics, and used the occlusal splint on a regular basis, which she felt had improved her sleep as well. The same satisfactory treatment result was maintained at the 1-year follow-up.

When the patient was advised that the planned removable partial could be constructed, she expressed disinterest. The reason she gave was that her headache, which had been her main problem, had ceased and that she had no difficulty in mastication. Accordingly, she was advised to gradually reduce the use of the occlusal splint, but if the headache returns she should resume its use on a more regular basis. She was also encouraged to visit the TMJ clinic, if necessary. 

Generally, the management of TMD has a good prognosis and most treatment studies report a clinical success rate of the order of 70-90% .⁶ The man- agement of this case was quite successful, but it is important to consider differential diagnostic aspects in the treatment of headache, which can sometimes be a symptom of a serious illness needing immediate medical treatment. In this case, however, the findings in the history and the clinical examination were supportive of TMD as the primary etiology of the patien's condition.

To date, no clear association of occlusal factors with signs and symptoms of TMD has been scienti- fically demonstrated.⁵⁷ Therefore, a conservative and reversible approach, that is, counseling, occlusal splints, muscle exercises, in the management of TMD should be advocated.

In well-controlled clinical studies, it has been consistently shown that an occlusal splint is very efficient and superior to the effects seen with placebo treatment or in untreated controls.⁷ The clinical efficacy of an occlusal splint, while not in question, still remains unexplained and the need, if any, for follow-up therapy is much debated.⁸

In patients with TMD as well as lost posterior support, as in the case reported, the occlusal splint should additionally provide molar support. Ideally, follow-up definite therapy should include the pro- vision of a removable partial denture in order to improve masticatory function, and reduce TMJ loading. The risk of development of TMJ osteoarthrosis may also be reduced.⁹ However, our patient did not accept such an option, and was instead called for regular assessments and invited to contact the TMJ Clinic should there be any re-occurrence of the problem. Consequently, the contradictory treatment results reported from studies using occlusal equilibration in the treatment of TMD are not surprising. Its effectiveness may well be attributed to the placebo effect.