DEGENERATIVE DISEASE OF THE TEMPOROMANDIBULAR JOINT IN YOUNG PERSONS. Introduction

Transcription

1 British Journal of Oral Surgery 17 ( ), DEGENERATIVE DISEASE OF THE TEMPOROMANDIBULAR JOINT IN YOUNG PERSONS HUGH Ocus, B.D.s., F.D.S. Basingstoke District Hospital Summary. The majority of cases of temporomandibular joint pain that are referred to the consultant dental surgeon are diagnosed as pain-dysfunction syndrome, a term first suggested by Schwartz (1959) and nowprobablythemost widely accepted. Another relatively common problem isdegenerative disease or osteoarthrosis, and although this generally affects an older age group than pain-dysfunction syndrome, its occurrance in the younger patient is by no means a rarity and is further evidence that the two conditions are expressions of the same problem, that is repetitive overloading of the joint. It is proposed that this should be termed mandibular stress syndrome. Introduction Osteoarthrosis of the temporomandibular joint Toller (1973) published a report of an investigation into the cases of 1573 patients with a temporomandibular joint problem. One hundred and thirty of these, that is 8 per cent were diagnosed as having degenerative lesions and, owing to the different clinical course of the mandibular disease from that occurring in other joints, he suggested that the condition should be referred to as temporomandibular arthropathy. The age distribution of these patients is shown in Fig. 1, the mean being about 53 years. Females were affected six times as frequently as males and this was compared with the even distribution found in generalised cases of the disease and the 3: 1 female/male ratio in pain-dysfunction syndrome. The principle clinical findings in degenerative disease of the temporomandibular joint are joint pain on movement or biting, which may limit mandibular function, joint tenderness on palpation, and crepitus, both audible and palpable. Although not always present in the early stages of the disease, radiographic changes almost always become evident and generally clinch the diagnosis. The most frequent findings are erosions of the antero-superior surface of the condyle (Fig. 2), only rarely are bony proliferations seen. It is uncommon for osteoarthrosis to be active bilaterally in the temporomandibular joint, this usually being a feature of rheumatoid arthritis which, if suspected, may be ruled out by a normal erythrocyte sedimentation rate and negative serology. In the absence of, or at the most conservative treatment, the condition runs a natural course over a period of between one and three years. The majority of cases present with severe symptoms which last for about nine months but which gradually burn out leaving little or no disability. The progress of the lesion may be demonstrated by serial radiographs (Toiler, 1973; Ogus, 1978), an example of which is described later in this paper. It has now been generally agreed that osteoarthrosis is a degenerative lesion brought about either by an increase in the functional demands on essentially healthy tissue, or by a deterioration in the functional capacity of the tissues themselves (Lancet, (Received 21 February 1978; accepted 18 April 1978) 17

2 18 HRITJSH JOURNAI. OF ORAL SURGERY IO x, IDYEARS AGE WHEN FIRST SEEN FIG. 1. The age distribution of 130 patients diagnosed as having osteoarthrosis of the temporomandibular joint (Toller, 1973). FIG. 2. An erosion of the antero-superior surface of the mandibular condyle.

3 DISEASE OF THE TEMPOROMANDIBULAR JOINT 19 NORMAL JOINT / Repetitive Overload. ; Functional Capacity Exceeded \ \ J Load OSTEOARTHROSIS FIG. 3. Diagram illustrating the aetiology of osteoarthrosis. Functional Capacity Reduced 1. Age 2.R.A. 3. Idiopathic 1973). In other words, as demonstrated in Figure 3; breakdown of the joint may occur when the tissues are subject to repetitive overload in excess of their functional capacity, or when they are subject to normal loads where this functional capacity is reduced as part of ageing or some other factor. Rheumatoid arthritis has been included here because recent research into the problem (Ogus, 1975) has shown that the temporomandibular joint is affected in at least two-thirds of all cases of the disease. It is now believed that many of the radiographic findings in the joints of these patients are not indicative of rheumatoid arthritis but rather of degenerative disease. Indeed it has been frequently found that condyles removed from patients with chronic rheumatoid arthritis are histologically reported as osteoarthrosis. Therefore it seems likely that following rheumatoid arthritis there is a deterioration in the functional capacity of the joint tissues and degenerative change takes place, even in response to normal loading. Investigation Method Study of the histogram (Fig. 1) which shows the ages at first presentation of cases diagnosed as degenerative disease of the temporomandibular joint, reveals a feature that requires further consideration. There is a secondary peak of 11 cases between the ages of 20 and 25. Furthermore, nearly one-third of the patients are under 40, a group one would normally associate with pain-dysfunction syndrome. The series was collected over 17 years and in the last four years a further 12 patients, under

4 20 BRITISH JOURNAL OF ORAL SURGERY the age of 25, have been diagnosed at Mount Vernon Hospital as having mandibular osteoarthrosis. Their case histories have been reviewed. Table I Summary of the results of the investigation. Although all the diagnoses were originally pain-dysfunction syndrome, in each case degenerative disease was later confirmed radiographically. Case No. Patient Sex Age Click Lock Symptoms Pain Crepitus -1 Treatment 1 c.c 2 A.G. 3 S.C. 4 CC. 5 AX 6 L.M. 7 G.L J.P. D.P. S.V. F 14 F 15 F 15 M 18 F 18 F 20 F 21 F 21 F 22 F 23 t t Right condylectomy Right condylectomy Left capsular rearrangement Right condylotomy Left condylectomy, steroids Steroids Steroids Case Histories (Examples) Case 4. A typical example of the problem is illustrated by C. G., a 20-year-old male whose symptoms of pain and stiffness failed to respond after two years of routine conservative therapy. The first X-ray (Fig. 4, ) shows no abnormality. Nine months late1 ( ) an obvious erosion was present which slowly resolved with conservative therapy. The latest X-ray (Fig. 5) shows a healed condylat surface. Case 7. G. L., a 20-year-old female who was first seen in April She gave a two year history of a temporomandibular joint problem which had started with a click on the left side. It had steadily become worse and she was now having pain from both sides, very severe on the left, which was waking her at night. Up until now the whole range of treatments had been prescribed (Table II). Her medical history was unremarkable and she had no symptoms from other joints. Her only hospital admission had been for the removal of third molars two years earlier. On examination there was no clicking or crepitus from either joint but she was tender on both sides, especially the left. X-ray revealed a somewhat flattened surface on the right, possibly a healed condyle, but erosions were present on the left (Fig. 6). R.A. latex test was negative and her E.S.R. was within normal limits. Although she had been re-assured that the condition would resolve naturally,

5 FIG. 4a (top left), b (top right), c (bottom left), d (bottom right). Radiographs from Case 4 illustrating a typical progression of an erosive lesion of the mandibular condyle. FIG. 5. The final radiograph from Case 4 illustrating the healed condyle.

6 Table II A list of the treatments prescribed in the management of Case 7 1 Remedial exercises. 2 Shortwave diathermy. 3 Bite appliances, three attempts. 4 Ultrasonic treatment. 5 Indocid. 6 Valium. 7 Removal of 3rd molars. 8 Jntracapsular injections of hydrocortisone. FIG. 6. Radiographs from Case 7 showing a healed condyle (R) and degenerative changes (L) the symptoms were not improving and life was becoming quite miserable. Surgical treatment was thus considered and in view of her X-ray findings it was decided to carry out a high condylectomy on the left and a condylotomy on the right. The operation was performed in May 1977 via a pre-auricular approach and intermaxillary fixation applied. The patient made very good progress and the I.M.F. was removed three weeks later. Her occlusion was satisfactory and her discomfort minimal. The resected specimen (Fig. 7) was reported as follows: Sections show a gross defect in the articular cartilage exposing underlying bone. There is fibrillar degeneration of the cartilage at the margins of the defect. There are a few areas of thin degenerative cartilage in the floor of the defect (Fig. 8) and a little fibrosis in the immediate subjacent marrow spaces. This is a typical picture of degenerative joint disease.

7 DISEASE OF THE TEMPOROMANDIBULAR JOINT 23 FIG. 7. The resected specimen from Case 7 showing an irregular condylar surface with a deep erosion anteriorly (arrowed). FIG. 8. Histological section through the condyle from Case 7 as shown in Fig. 7. Results A summary of the results is shown in Table I and it will be noted that all 12 patients, 11 female and one male, had been initially diagnosed as having pain-dysfunction syndrome. Five had developed crepitus before degenerative disease was confirmed on X-ray and seven were only diagnosed radiographically when they failed to respond to routine conservative therapy. Three patients were treated for the degenerative condition with intracapsular steroid. Two of these were successful but the third failed after an initial improvement. Three patients were operated on, including the one whose steroid therapy had failed. The remaining seven patients were all treated

8 24 BRITISH JOURNAL OF OKAI. SURGERY conservatively with reassurance. rest, bite planes and analgesia. Their conditions have all resolved. Discussion From Toiler s (1973) series and the subsequent cases from his unit added, the occurrence of osteoarthrosis in the temporomandibular joints of young persons is therefore not a rare finding, and since all the cases in this series first presented with symptoms typical of pain-dysfunction syndrome, it is possible that both conditions are expressions of the same problem; that is repetitive overload of the joint system. The hypothesis is illustrated in Fig. 9. As stated previously, degenerative change takes place when the joint is subject to Iepetitive overload in excess of its functional capacity, 01 when it is subject to normal loads where this functional capacity is reduced. The initial reaction to the overload however, may frequently be expressed clinically as clicking (meniscal hesitation; Toiler, 1976) and mandibular deviation. These early signs of dysfunction may progress to spasm of the masticatory muscles resulting in stiffness and locking of the jaw, and pain, both on account of the spasm and from within the joint itself. This is a reversible situation as if the overload is relieved then the symptoms subside and function returns to normal, If, however, the overload should continue and the functional capacity is either exceeded or becomes reduced, then, even in young persons, irreversible degenerative change takes place. Although, as shown in the diagram, not all cases of osteoarthrosis are preceded by pain and dysfunction, the fact that NORMAL JOINT R&titive Normal, Overload Load, Capacity Exceeded \ ) Capacity Reduced 1. Age 2. R.A. 3. Idiopathic FIG. 9. Diagram illustrating the relationship of pain and dysfunction to degenerative disease of the temporomandibular joint.

9 DISEASE OF THE TEMPOROMANDIBULAR JOINT 25 degenerative change is more frequent in the older age group is merely an indication of the decline of the functional capacity with age. One of the difficulties in accepting this hypothesis has been in regarding the temporomandibular joint as a load bearing structure. It had previously been concluded that the joint was not histologically or mechanically adapted to this purpose (Robinson, 1946). Barbenel (1974) however, following the suggestions of Craddock (1951) and Roydhouse (1955) proposed quite the opposite. He produced evidence to show that even under normal conditions, the joint is load bearing, and thus presumably, in certain situations, subject to overloading. The aetiology of the overload is most frequently a clenching or similar habit in an anxiety or depressive state although occlusal factors probably play a part in that patients with certain malocclusions are more susceptible to the problem. In patients with Angle s Class II division 2 relationships for example, the occlusion pathways are more rigidly defined and the greater proportion of the load is diverted to a small area of the joint surface rather than being spread over wider areas of the articular system. Banks and Mackenzie (1975) have suggested that situations, such as loss of molar support or change in the vertical dimension of the bite, alter the theoretical direction of the forces acting on the mandible and consequently the load bearing factors operating through the condylar head. Further evidence in support of the hypothesis has been found in ultra-microscopic studies of the condyle (Toller, 1977). Changes found in severe cases of pain-dysfunction syndrome are indistinguishable from those in early cases of osteoarthrosis. The separate terms of pain-dysfunction syndrome and osteoarthrosis of the temporomandibular joint are therefore misleading and it would aid both diagnosis and treatment if they were to be considered as a single condition. It is proposed that this should be the mandibular stress syndrome for this title is illustrative not only of the increased mechanical load on the joint itself but also of the most frequent aetiological factor, anxiety. It might be argued that in our series, three out of 12 patients is a high proportion to have been treated by surgery, but it must be remembered that these three patients are only a small fraction of those in this age group who had been treated for a temporomandibular joint problem over the same period. Management of the problem should therefore be concerned with the identification of the cause or causes of the overload and their relief. Indeed the concept explains the rationale behind all the contrasting but often successful methods of treatment of pain-dysfunction syndrome. Anti-anxiety or anti-depressant drugs act on the primary cause. Bite appliances, of whichever variety, act mechanically to lessen the load being transmitted to the joint surfaces, and occlusal therapy may redirect and diffuse this load. Acknowledgements 1 would like to express my appreciation for the help and encouragement in this work that I received from the late Paul Toller. My thanks also to Mr Ronald Blake and Mr Robert Toy, photographers at Mount Vernon and Basingstoke hospitals, and the Editor, British Dental Journal, for permission to use Figure 1. References Banks, P., & Mackenzie, I. (1975). Condylotomy - a clinical and experimental appraisal of a surgical technique. Journal of Maxillo-Facial Surgery, 3, 170. Barbenel, J. C. (1974). The mechanics of the temporomandibular joint - a theoretical and electromyogaphical study. Journal of Oral Rehabilitation, 1,19. Craddock, F. W. (1951). A review of Costen s syndrome. British Dental Journal, 91, 199. ancet (1973). Editorial, 2, 1131.

10 26 BRITISH JOURNAL OF ORAL SURGERY Ogus, H. D. (1975). Rheumatoid arthritis of the temporomandibular joint. British Journal qf Oral Surgery, 12,275. Ogus, H. D. (1978). Degenerative disease of the temporomandibular joint and pain-dysfunction syndrome. Proceedings of the Royal Society of Medicine, Robinson, M. (1964). Theory of reflex controlled non-lever action of the mandible. Journalof American Dental Association, 33, Roydhouse, M. (1955). Upward force of the condyles on the cranium. Journal of American Dental Association, 50, 166. Schwartz, L. (1959). Disorders of the Temporomandibular Joint. Philadelphia: Saunders. Toiler, P. A. (1973). Osteoarthrosis of the mandibular condyle. British Dental Journal, 134, 223. Toiler, P. A. (1976). Non-surgical treatment of dysfunctions of the temporo-mandibular joint. Oral Sciences Review, 1, 70. Toiler, P. A. (1977). Ultrastructure of the condylar articular surface in severe mandibular paindysfunction syndrome. International Journal of Oral Surgery, 61, 297.