The plethora of symptoms that are commonly associated with temporomandibular joint dysfunction are generally characterized by pain in the area of the temporomandibular joints, and pain in the masticatory muscles and the functionally associated myofascial structures of the head and neck. Along with painful symptoms, it is also common to find limitation of movement of the jaw, cervical and thoracic spine, and shoulder girdle. Viewed as a whole, chronic pain within the orofacial region can be a persistent and debilitating disorder. In term of numbers of patients affected, a generally accepted figure of about 10 - 12% of the population is presented in most studies.(1). To what degree these persons are debilitated by their TMD problems is not known and can only be determined on a case-by-case basis by individual interview and assessment. Orofacial pain, craniomandibular pain, temporomandibular joint pain, myofascial pain-dysfunction syndrome, and orofacial pain-dysfunction are just a few of the many terms encountered in the literature of the disorder. Whatever term is currently popular, they all generally refer to an intimately related set of signs and symptoms. Attempts to define one particular term that would encompass all eventualities have not been very successful, because of variation in the nature of the disorder itself. One patient can have fairly limited problems associated with a distinct anatomic area, while another can have a multitude of symptoms involving a much larger anatomic region of the body. Causation is multifactorial and can be associated with minute occlusal discrepancies, or run the gamut to serious physical injuries brought about by many forms of accidental trauma - a couple of the more common being falls and automotive accidents. When it comes to the analysis and categorization of many painful symptoms, the common tendency is often moving everything into a larger overall general classification; however, in the case of head pain, the tendency seems to lean toward dissecting the larger entity into a mass of subgroupings. While not the only possible initiator of head pain, temporomandibular joint dysfunction is often a common entity in many cases of head pain - whether it arises from developmental errors (poor anatomy), disease processes (dental caries, unrestored tooth loss), attrition (wear and tear), trauma, systemic stress, or degenerative changes associated with age. The sudden appearance of symptoms in a previously asymptomatic individual is often only a sign that some specific triggering event has upped the ante, and overwhelmed an individual's ability to cope with an accumulation of minor disfunctions.
While the etiology (2) of temporomandibular joint dysfunction is complicated by a host of factors, the diagnosis of the problem is equally difficult, although perhaps somewhat overcomplicated, by the myriad of diagnostic procedures, both appropriate, and possibly inappropriate (3), currently available to the clinician. Treatment is also made complicated by the sheer mass of treatment strategies currently in vogue (4) which can range from minor occlusal adjustment, occlusal reconstruction, orthodontic treatment (including orthognathic surgery) through invasive surgical procedures of the joints (5), to behavior modification modalities such as biofeedback(6), psychotherapy (7), and relaxation therapy (8). Although specifically excluded from the former list strictly to make a point, the most common and most utilized treatment of temporomandibular dysfunction and head pain in general remains that of chemotherapy, including analgesic and mood altering drugs dispensed by the tons.
At first glance it would appear that a so-called "average" TMD patient enters the treatment arena only to find himself facing a somewhat disorganized professional team dispensing therapies from every direction of the therapeutic compass. This is a problem with all of the professions that generally attempt treatment of TMD. Everyone seems to have a different therapeutic offering, and this leads to confusion - both on the part of the patient, and the professionals, too. The United States House of Representatives even got into the act in 1984 when it mandated that studies be done regarding painful conditions, including myofascial pain syndrome, and that reports be generated that could be used by the insurance industry, insurance adjusters, disability examiners, and clinicians to improve the state of knowledge and appreciation of the problem. The Institute of Medicine came out with a report called: Pain and Disability, Clinical, Behavioral and Public Policy Perspectives (9), in 1987. The jury is still out when it come to assessing whether this document has improved practical matters for the typical patient affected with the problem.
Taken as a whole, clinicians from many disciplines probably do a fairly decent job in treatment of TMD at the time it shows it's face in the individual clinician's office. The main reason for this conclusion may be attributed more or less to pure doggidness on the part of the individual clinician and equal persevearance on the part of the individual patient. Wouldn't it be more reasonable and thus more efficient in the end to attempt to standardize therapeutics in some small manner? Dentistry is thought to be uniquely positioned to be the major therapeutic agency for the treatment of TMD problems, but cannot accept the total treatment responsibility for the management of the disorder as a practical medical matter. Too often, effective treatment demands participation from several professional specialties in order to provide the best care for the patient. Basic treatment modalities in the dental setting include occlusal adjustment, occlusal orthotics, orthodontics, occlusal reconstruction/rehabilitation, active trigger point therapy, and surgical management. The medical profession must supply important support functions in diagnostic procedures such as x-ray, CT, and MRI imaging and portions of the overall treatment plan that may include anesthesia and surgery, additional pain management, and psychiatric therapy. The new kid on the block, oral implantology, has also been added to the armamentarium in the last few years, and can provide important reconstructive benefit to the patient compromised by tooth loss.
The usual sequencing of active TMD therapy in the dental arena is to start with conservative treatment of a reversible nature utilizing what has been termed, physically based modalities, that is, bite splints, adjunctive chemotherapeutic agents, such as analgesics, anti-inflammatory agents, muscle relaxants, mood elevators, and trigger point therapy. It is best to avoid use of "tranquilizers" of the benzodiapame family, as these agents inhibit Stage 4 sleep and can interfere with restful sleep which many of these patients may need as part of their overall treatment. Physical modalities also imply the acceptance of a philosophical model of the disorder that assumes that the patient's complaints are the result of a specific disease state, or specific pathological change in the associated anatomic structures. Diagnostic tests are often designed to confirm the existence of an objective state of physical damage and/or physical impairment. A positive finding in testing confirms that a specific organ, or organ system is to some degree unable to perform it's basic biologic function within acceptable, or normal limits. Therapeutic procedures are then directed at improving, even correcting, the specific organ pathology or dysfunction disclosed in the testing. This represents the application of physical medicine to solve a specific problem.
An area where the dental profession appears to have some significant therapeutic limitation is the general psychosocial aspects of the disorder. While it is easiest to jump right in and produce definitive therapeutic results with physical modalities in the majority of TMD cases, a significant percentage of patients fail to achieve significant clinical success through application of physical modalities alone. The major problem in this approach is the failure to look for and identify important psychological and pyschosocial aspects that may be present in the patient. The problem is often seen in retrospect when the clinician begins to realize that the patient's complaints and description of his ailments are not commensurate with the clinician's observations about the degree of existing pathology.
Failing to recognize that a significant number of chronic TMD patients exhibit a complex interrelationship of pathology, psychologic and social factors is a common fault in the dental arena. A more accurate clinical picture emerges when the dental clinician integrates pathologic changes in the articulation and supporting musculature, psychological status, and the social and cultural components that really shape the individual patient's awareness of and response to his condition. Disease is basically definable as an objective biologic event that causes a physical or biochemical disruption of specific bodily structure, or organ systems related to pathologic anatomic or physiologic changes. The chronic pain patient may be thought of as having both a disease, and also an illness. In this context, an illness is interpreted as meaning a subjective, or very personal encounter with a disease process which also produces physical discomfort, frank pain, emotional distress, changes in behavior, and psychological and social disruption. Degree of illness is mainly a self attribution that a patient is suffering from something, and is difficult to quantify. The key phrase is "personal encounter", because this is the single factor that complicates cookbook approaches to assessing and treating existing pathology in a mechanical sense. Individual patients manifest their illness based on their own awareness and understanding of their specific disease and how that disease process disrupts their individual circle of familial, or wider social relationships. The individual's perception of pain results in a complex cognitive-emotional appraisal process during which the pain sufferer assigns his own personal meaning to the pain itself. Eventual decisions are made as Standard evaluation tests to assess the individual sense of well-being and the degree of both physical pain and psychologic impact have been developed over years, and can be of some value to the clinician dealing with these patients (10,11).
In some cases a referral for evaluation and counseling by a clinical psychologist can be critical to achieving maximum therapeutic effect and helps the dentist to better appreciate the pyschosocial aspects of chronic pain. The importance of assessing the personal, psychological, and social aspects of chronic pain cannot be overemphasized. A clinical psychologist might test a patient using the MPI (Multidimensional Pain Inventory) to help distinguish the degree of psychosocial dysfunction that exists with chronic pain (12). With the test data, it is often possible to separate the patient who has significant clinical depression associated with their pain problem from other individuals who are psychologically better at coping with pain and discomfort. This is based on the often observed fact that one patient's pain and dysfunction may not be equal to the degree of observed pathology. Realizing this, the clinician should be able to make some distinctions, or classification of a patient's actual physical impairment, his actual disability, and his actual dysfunction. This enables a prediction of sorts about an individual patient's perception of his pain problem, what motivates the patient in regard to solving his problem, and a general assessment of what the patient's behavior will, or will not be, when it comes to cooperating with a treatment plan.
Dworkin and LeResche (13) have outlined a two-fold approach to classification of TMD which they call the Research Diagnostic Criteria. The RDC uses one path to classify TMD according to clinical findings such as measurements of jaw opening, joint sounds, and results of manual palpation of the musculature; while another puts direct emphasis on pyschosocial classification of the patient by assessing the patient's interpretation of chronic pain, their degree of dysfunction and depression, and somatization. Use of this two axis approach to classification enable a better understanding of the personal effects of the disorder on the individual patient. The RDC uses a self completed Symptom Checklist to enable the clinician to derive individualized pyschosocial information about the patient by scoring the self assessment according to scales provided in the Axis II Symptom Checklist 90-R, or SCL-90-R scale. One set of results enables an assessment of depression, while another enables assessment of the degree of somatization. While both are clinically relevant, somatization is often a better indicator when making a determination about how a patient reacts to their pain and dysfunction and how they may relate to the treatment provided. Somatization in this case specifically refers to a personality trait where the patient tends to report physical distress arising from what may be perceived symptoms, but which may not be consistent with measurable pathologic or physiologic findings. High somatization score may also indicate excessive and inappropriate sensitivity to physical symptoms and a difficult patient to treat, for as one symptom subsides, another may come to the fore.
While most dentists would likely accept as true a statement that "TMD is a chronic and progressive condition", fact seems to point to the opposite conclusion. Epidemiology of a truly chronic and progressive condition would show a population of TMD sufferers steadily increasing in numbers as the population ages; however, many studies seem to indicate that the condition seems to most afflict women in the general child bearing age group. There is no increasingly higher percentage of elderly patients with ever worsening, or chronically progressive TMD. The peak prevalence of TMD in the population, specifically around 10-15 %, appears in women of child bearing age, and then this drops to about 4-5 % in women at age 65. Analysis of this data seems to indicate that TMD must therefore be a self-limiting condition that just progresses to a certain point of demonstrable physical change, but that it doesn't get more severe with increasing chronicity. Whether this is a valid conclusion based on the available facts is not entirely clear, but personal observations seem to bear out a somewhat similar conclusion. In the case of traumatic injury associated with automobile accidents it is not uncommon to see head, neck, and shoulder pain as an immediate, intermediate, or late sequela to that trauma. Posttraumatic headache (PTH) is often seen in patients both with, and without obvious signs of intracranial or extracranial injury. Other injuries may honestly occupy the attention of the medical/surgical team for weeks and months after the trauma takes place. However, for those dealing with the sequela of trauma, it is not uncommon for us to see these patients many months after the initial injury. Some statistics indicate that PTH is a finding in as much as 45% of all types of head injury. Regardless, these symptoms are difficult to diagnose and treat, especially since all of the acute outward signs of injury may have healed (14). The end result of treatment started after a late diagnosis of post-traumatic head pain is often only a compromise at best, and every effort should be made to identify and treat patients with this condition as early as possible. If statistical evidence exists indicating that as much as 45% of all head trauma produces posttraumatic head pain, and that a high proportion of these patients exhibit temporomandibular dysfunction, a case exists for making early referral for evaluation and treatment a priority item.
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Copyright 1995 R. E. Brossman DDS, MS