Temporomandibular disorders

Temporomandibular disorders involve both the upper and lower jaw and may be related to certain diseases of the teeth, or they may be separate acquired or congenital diseases. Some diseases are developmental, others are forms of acquired inflammation, granuloma, positional anomalies or cysts and other unnatural formations on the jaw. There are diseases affecting both jaws, or only unilateral and localised disorders, and some are also diseases of the temporomandibular joint.

The jaw is a paired bone that is one of the largest bones in the human body. The jaw consists of an upper and a lower part, with the lower jaw sometimes called the temple. The canine is the only movable bone of the skull, which is connected to it by the temporomandibular joint. The mandible, also called the lower jaw or jawbone, consists of a body and a paired arm, and is originally a paired bone, but within a year of birth it fuses into a single unit. Both the upper jaw and the lower jaw are part of a single unit affected by jaw disease.

The upper dentary is located in the alveolar process of the maxillary bone, similarly the lower dentary is also located in the alveolar process in the bone bed. The maxilla also forms the hard palate of the oral cavity and the base of the nasal cavity and contains the paranasal sinus, the so-called maxillary sinus. Diseases of the jaw thus affect the lower jaw, the upper jaw, the temporomandibular joint itself, and many times are also related to other diseases, whether of the oral cavity or other related cavities or hard and soft tissues.

Position and size anomalies

The jaws are quite often affected by various anomalies, either in the position of the jaw bones or in the size of the individual parts of the jaw. For example, hyperplasia or hypoplasia of both the upper jaw and the canine occurs, or a pathological condition called macrognathism or micrognathism occurs. Jaw abnomarmalities, such as asymmetry, prognation or retrognathia of the jaws, may also occur in relation to the skull base. Anomalies of the position of the succeeding dental arches sometimes occur in parallel.

In addition, diseases of this type affecting the jaw include dentofacial functional abnormalities and disorders such as abnormal jaw closure or malocclusion acquired during life for various reasons such as faulty chewing, mouth breathing or other unnatural jaw movements. Miscellaneous anomalies also include malocclusions that are caused by an unnatural change in the position or size of the jaw bones.

Projections of the jaw position, i.e. protrusion, are very common. In this case, there is a striking protrusion of the jaws and it is a developmental anomaly of the upper jaw, when there is a roof-like protrusion of the teeth. The opposite is retrognathic jaws. These disorders can be followed by bite disorders, which are only a consequence of them. In the case of a serious anomaly, only surgical treatment of the pathological condition is necessary, which is, however, rather complicated.

Several anomalies can also be treated conservatively by wearing various appliances or braces, but these are only minor disorders of a local nature. These are developing malocclusions, i.e. an incorrect or defective bite resulting from bad habits or malocclusion. With these forms, correct tooth alignment and jaw positioning is possible, with the secondary effect of helping with myofunctional disorders related to the jaw.

Functional abnormalities and disorders of the joint

In addition to the jawbone itself, several diseases also affect the temporomandibular joint. These include various disorders or functional abnormalities such as Costen's complex or Costen's syndrome, increased wear and tear of the temporomandibular joint, temporomandibular joint pain dysfunction syndrome or clicking jaw problems. The most common problems are Costen's syndrome and pain dysfunction syndrome.

Costen's complex is a disease named after the American doctor who described the disease more than 80 years ago. It is a malfunction of the connection between the lower jaw and the bones of the skull, and this disorder is related either to disorders of the joint itself, or to problems with the masticatory muscles or the incorrect position of the jaw. Most often, the triggering factors are stress or overall poor dental health. Typically, the condition manifests itself with pain, namely when yawning, chewing and pain in the ear.

The treatment is quite challenging as it is a complex disorder affecting both the joints and the dental disorders. Conservative treatment with pain point dressings and physical therapy is the most common treatment, but in some more serious cases surgical treatment is necessary. In addition, it is also necessary to introduce certain measures, especially in connection with the elimination of habits in the movement of the sledge and the like.

Common temporomandibular joint disorders include various bite problems, which may be crossed or deep, while arthritic disorders are relatively common, which includes myofacial pain dysfunction syndrome. This is a problem involving only the joint itself and its capsule, which is technically called intracapsular disorder. However, in addition to this type of disorder, extracapsular disorders involving adjacent structures can also interfere with and manifest in the joint.

Cysts and tumours

Various types of cysts or tumours affecting the jaws or their immediate surrounding tissues are also a problem and can often grow into the oral or other related cavities. It is not always possible to distinguish only cysts involving the jaws, as these also extend into other tissues, or, conversely, several cysts and tumours from soft and hard tissues extend into the jaws. These may be developmental odontogenic cysts, non-odontogenic cysts, direct jaw cysts or oral cysts.

The most common form of jaw cyst is traumatic, hemorrhagic, aneurysmal or nonspecific. In addition to it, cysts arising from the dental germ, cornified cysts, cysts arising from the palatal papilla and various dermoid, epidermoid, lymphoepithelial and other cysts also arise. In addition to the harmless cysts, tumors affecting the oral cavity also arise in some cases in the bones of the canine or maxilla, and the danger is that they manifest themselves late.

The tumours only become apparent at an advanced stage and can cause either jaw dislocation, wobbling or tooth loss and pain in the jaw or jaw area. They are most often discovered only after an X-ray examination, which is why such an examination of the jaw should be part of a preventive check-up. Dangerous are malignant tumours, which quickly metastasize to the surrounding tissues, are aggressive, often asymptomatic for a long time and can even cause death of the patient.

Cysts in the jaw and also in the surrounding cavities, for example, arise from defective tissue development, such as keratocysts, gingivacysts, eruption cysts, periodontal cysts or follicular cysts. Sometimes they also arise from an inflammatory background such as a radicular cyst or a recurrent cyst. Cysts are most common in the under 50s and many times grow painlessly, so that, like tumours, only an X-ray will detect them. Removal is only possible by maxillofacial surgery.

Inflammatory diseases

The jaw and related tissues are also very often affected by various acute and chronic inflammations, which are mainly manifested by pain and tenderness. These inflammations include, for example, osteitis of the jaw, which can be both acute and chronic, osteomyelitis of the jaw, which is a neonatal inflammatory disease in both acute and chronic forms, acute, chronic or suppurative osteoradionecrosis of the jaw is also common, and another type of inflammation called periostitis has similar forms.

A less common disease of an inflammatory nature that affects the jaw is also called jawbone sequestrum.In addition to the jaw itself, inflammation in these tissues can also be associated with inflammation of the tooth beds, which is called alveolitis of the jaw. Such inflammation also includes and alveolar osteitis or so-called dry bed. This is a condition where a blood clot does not form and the wound does not close after a tooth is extracted, and it is a relatively painful condition that must be addressed with drainage.

Osteomyelitis, for example, is a common inflammation and is a severe inflammation affecting the jaw bones.It is also a multifactorial disease, which is caused by an infection penetrating the hard tissues of the jaw and causing an immune reaction, which quite often results in a purulent form of inflammation. This inflammation accounts for almost one third of jawbone inflammation, and in the acute case there is a rapid onset of typical inflammatory symptoms. Treatment is aimed at removing the inflammatory and suppurative deposits.

Osteitis of the jaw is also a relatively common inflammation, which can also have an acute but also chronic form. It is a non-purulent inflammation of the jaw bone, which can have various causes, most often the passage of infection from some related soft tissue or cavity into the bone. It is an inflammation characterised mainly by soreness of the affected area, the inflammation being mostly local and unilateral. It affects the upper and lower jaw in approximately equal measure and treatment is largely local.

Developmental and other diseases

The jaws are also affected by various developmental disorders and diseases resulting from developmental defects. These include diseases such as Stafnes cyst, hidden bone cyst of the jaw, Torus mandibularis or central giant cell granuloma. In addition to these developmental disorders, common pathologies affecting both the lower and upper jaw include, for example, cherubism of the jaw, fibrous dysplasia, exostosis or unilateral condylar hyperplasia or unilateral condylar hypoplasia. These diseases also cause other related problems and defects.

For example, a malignant fibrous histocystoma can grow on the jawbone, which most often affects children up to the age of 15 years and can be found on the skull bone or on some long bones in addition to the jawbone. Similarly, an osteoma, which is a benign or benign mass, also growing on the jawbone, is composed of mineralised bone marrow with the presence of multiple osteocysts. It is a slowly evolving disease but causes external deformities.

A relatively common pathological condition is exostosis, which is a benign dislocation of the bone appearing symmetrically in the mandible. As long as it is not too bothersome and does not interfere with the functionality of the entire sled, it usually does not need to be acutely addressed. The problem is if it causes disease or deformity of the teeth. The disease is benign and is caused by a local multiplication of bone cells that has no infectious cause. It progresses over a long period of time, even several years, so it is not always detectable at first sight.