Temporomandibular Joint Dysfunction Syndrome

Temporomandibular joint dysfunction Syndrome or Facial Athromyalgia refers to problems that affect the joint between the lower jaw and the base of the skull and the muscles of mastication. Increased activity of the muscles of mastication causes them to spasm and become hypertonic leading to pain in the muscles and the affected tempormandibular joint. Facial Athromyalgia is not usually a serious condition, but symptoms can impact significantly on quality of life. Doctors sometimes also refer to the condition as Temporomandibular pain disorder. It has been estimated that approximately 20-30% of the adult population will experience a TMJDS at some point.

What are the symptoms?

TMJDS can cause:

clicking at the affected Temporomandibular joint whilst opening the mouth or whilst chewing
muscle pain/spasms around the jaw
pain in front of the ear that may spread to the cheek, ear and temple
difficulty opening the mouth – the jaw may feel tight, as if it is stuck, making eating difficult
headache or earache
Increased occlusal/incisal wear of teeth
presence of several abfraction lesions (small cavities on teeth by the gum margin) making the teeth hypersensitive to thermal stimuli
Scalloping of the lateral borders of the tongue

What are the causes?

The main causes of TMJDS are:

clenching your jaw or grinding your teeth during sleep (dental parafunctioning), which overworks the jaw muscles and puts pressure on the joint. This habit is thought to be caused by stress/anxiety. Dental parafunctioning is a common habit and 90% of the population is thought to dental parafunction from time to time.
wear and tear of the inside of the jaw joint, usually caused by osteoarthritis
a disease causing inflammation of the jaw joint, such as rheumatoid arthritis
injury to the jaw joint, for example after a blow to the face or surgery

How is TMJDS treated?

Based upon a thorough extra-oral and intra-oral examination along with detailed history taking, a diagnosis of TMJDS can be made.Lifestyle changes

There are a number of self-help measures that can help improve TMJDS, including:

resting the joint by eating soft food and avoiding chewing gum
holding a warm flannel to the jaw after doing a few gentle jaw-stretching exercises
avoiding opening the joint too wide
massaging the muscles around the joint
relaxation exercises to relieve stress (people tend to clench their jaw when stressed)
not resting your chin on your hand

Mouth guards (Occlusal Splints)

An occlusal splint is a thin shield of plastic that is ‘U’ shaped and fits snugly around either the upper or lower teeth. It separates the upper and lower teeth and in so doing prevents the upper and lower teeth from grinding against each other and protects the teeth from wear. It also encourages the lower jaw to go into a relaxed retruded position. It is also thought to interfere with proprioceptive feedback from the teeth and in so doing encourages the lower jaw to relax. The splint can be made out of a hard material like acrylic or a soft material like vinyl. A michigan type splint fits on the upper teeth and is generally more comfortable. A lower splint like a tanner appliance fits around the lower teeth. Splints are generally worn through the night as most dental parafunctioning is done through the night, whilst asleep. The hard acrylic splint can be shaped to have an ideal bite surface shape. It has a flat posterior bite plane that helps to eliminate occlusal interferences and has a shallow anterior slope/guidance that helps separate the posterior teeth in excursive movements. We custom make the hard acrylic michigan splint on a special mechanical device called a Denar semi-adjustable articulator. The relationship between the upper teeth, TMJ and lower teeth for an individual patient is transferred to this device which then mimics the excursive movements of that individual patient. In this way a customised occlusal shape can be incorporated in the occlusal splint for that individual patient.