THE ROLE AND SIGNIFICANCE OF COSTEN’S SYNDROME IN DYSFUNCTIONAL CONDITIONS OF THE TEMPOROMANDIBULAR JOINTS
Authors: Makeev V.F. , Telishevska U.D. , Telishevska O.D. , Mykhailevych M.Yu. 
Published: September 2020

Temporomandibular joint disease (TMJ) is one of the most pressing problems of modern dentistry, on the one hand, the frequency of pathology of the temporomandibular joint, and on the other hand - the complexity of diagnosis.

In the medical specialty "dentistry" there is no section where there would be as many debatable and unresolved issues as in the diagnosis and treatment of diseases of the temporomandibular joints.

Aim of the research. Based on the analysis of sources of scientific and medical information to determine the role and place of "Costen's syndrome" in the pathology of the temporomandibular joints.

Results and discussion

The term TMJ dysfunction has up to 20 synonyms: dysfunction, muscle imbalance, myofascial pain syndrome, musculoskeletal dysfunction, occlusal-articulation syndrome, cranio-mandibular TMJ dysfunction, neuromuscular and articular dysfunction.

Finally, in the International Classification of Diseases (ICD-10), pain dysfunction of the temporomandibular joint has taken its place under the code K0760 with the additional name "Costen's syndrome", which is given in parentheses under the same code.

Thus, such a diagnosis as "Costen's syndrome" is not excluded in the International Classification of Diseases.

The first clinical symptoms and signs of TMJ were systematized in 1934 by the American otorhinolaryngologist J. Costen and included in the special literature called "Costen's syndrome".

This syndrome includes: pain in the joint, which often radiates to the neck, ear, temple, nape; clicking, crunching, squeaking sound during movements of the lower jaw; trismus; hearing loss; dull pain inside and outside the ears, noise, congestion in the ears; pain and burning of the tongue; dizziness, headache on the side of the affected joint, facial pain on the type of trigeminal neuralgia. The author emphasized the great importance of pain and even singled out "mandibular neuralgia."

The criteria proposed by McNeill (McNeill C.) in 1997 are somewhat different from those described in ICD-10: pain in the masticatory muscles, TMJ, or in the ear area, which is aggravated by chewing; asymmetric movements of the lower jaw; pain that does not subside for at least 3 months.

The definition of the International Headache Society is similar in content.

Anatomical and topographic study of the corpse material suggested the presence of a structural connection between the TMJ and the middle ear. According to some data, in 68% of cases the wedge-shaped mandibular ligament reaches the scaly-tympanic fissure and the middle ear, and in 8% of cases it is attached to the hammer. In addition, several ways of spreading inflammatory mediators from the affected TMJ to the middle and inner ear, which causes otological symptoms, have been described.

It should be noted that there are certain prerequisites for the mutual influence of the structures of the cervical apparatus, middle and inner ear and upper cervical region at different levels: embryological, anatomical and physiological.

At the embryological level. It is confirmed that from the first gill arch develops the upper jaw, hammer and anvil, Meckel's cartilage of the lower jaw, masticatory muscles, the muscle that tenses the eardrum, the muscle that tenses the soft palate, the anterior abdomen of the digastric muscle, glands, as well as the maxillary artery and trigeminal nerve, the branches of which innervate most of these structures.

At the anatomical level. Nerve, muscle, joint and soft tissue structures of this region are located close enough and have a direct impact on each other. The location of the stony-tympanic cleft in the medial parts of the temporomandibular fossa is important for the development of pain dysfunction.

At the physiological level. A child who begins to hold the head, the functional activity of the extensors and flexors of the neck gradually increases synchronously with the muscles of the floor of the mouth and masticatory muscles, combining their activity around the virtual axis of the paired temporomandibular joint.

In addition, the location of the caudal spinal nucleus of the trigeminal nerve, which is involved in the innervation of the structures of the ear, temporomandibular joint and masticatory muscles at the level of the cervical segments C1-C3 creates the possibility of switching afferent impulses from the trigeminal nerve to the upper cervical system. Innervate the outer ear, neck muscles and skin of the neck and head. Also important are the internuclear connections in the brainstem, which switch signals between the vestibular and trigeminal nuclei.

That is why the approach to the treatment of this pathology should be only comprehensive, including clinical assessment of the disease not only by a dentist or maxillofacial surgeon, but also a neurologist, otorhinolaryngologist, chiropractor, psychotherapist with appropriate diagnostic methods and joint management of the patient.