Temporomandibular Disorder (TMD)
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Temporomandibular joint disorder (TMD) is a broad term that includes disorders of the temporomandibular joint and its associated anatomy.
The condition may be intra-articular due to inflammation, internal structural changes (internal disturbances), or degeneration, or extra-articular due to imbalance or overactivity of the jaw muscles (usually the masticatory or cervical muscles). have a strong correlation Relationship between cervical postural dysfunction and TMD. There are many other conditions that can cause pain in the TMJ area. It is important to make an accurate diagnosis to ensure that the correct treatment is given and that potentially serious problems are not overlooked.
In an earlier study of postmortem specimens , it was found that in more than half of the specimens, the lateral pterygoid was attached to the meniscus of the joint capsule and medial to the fovea of the condyle. This suggests that muscle may have a specific contribution to TMD.
See the Muscles of Mastication page for more information on their anatomy.
Causes of TMD
1. Inflammation in the joint usually caused by direct trauma, such as a blow to the jaw or jaw Indirect trauma, such as whiplash Severe chewing molars (bruxism) Jaw clenching or decreased tooth height due to worn or missing teeth.
- Synovitis – The synovial membrane or joint capsule may become inflamed. Pain at rest, limited range of motion, or pain at end of range of motion is common.
- Postdiscitis – The retrodiscal tissue (where the joint disc connects to the back of the mandibular fossa) is rich in blood vessels and innervation and can cause severe pain if inflamed. The jaw may deviate from the painful side when resting and opening.
2. Internal disturbance describes a situation where structural changes occur within the joint. This can be caused by direct trauma, such as a blow to the jaw or a fall on the jaw, indirect trauma, such as whiplash, prolonged clenching or grinding of heavy objects or chewing hard or for prolonged periods of time Openings, such as dental surgery or general anesthesia.
- Disc displacement – The disc can be displaced in any direction, but most commonly it is forward. The disc is pushed forward and bunched up during opening. At some point within the range, the disc will reposition or shrink itself causing an audible or Obvious click. The jaw usually deviates to the affected side.
- Displaced disc without reduction – In this more severe version, the disc will not reset, causing pain and loss of range. This is called latch-up. The jaw usually deviates to the affected side. There will be no clicking, but patients may report that there is a clicking sound at the time When their jaws lock.
- Osteoarthritis can occur in the temporomandibular joint. It can usually be seen on plain radiographs or osteopathic tomography (OPG) as the condylar heads are flattened, often with some osteophyte formation. MRI is more informative by views taken in open and closed positions. This shows the position of the joints and discs at the beginning and end of the range. Crepitus can usually be felt or heard with a stethoscope. It can be an age-related degeneration, usually in the 50s, or secondary to trauma that occurred at a young age.
- Inflammatory joint diseases can affect the TMJ, including rheumatoid arthritis, ankylosing spondylitis, infectious arthritis, Reiter’s syndrome, and gout .
4. Hyper mobility
- It causes excessive forward movement of the jaw and joint disc. This will cause the jaw to deviate from the affected side. There is usually some clicking in the TMJ, which may or may not be painful. Hyperactivity may be associated with connective tissue disorders such as Conditions such as Marfan syndrome or Down syndrome and cerebral palsy. Chronic hypermobility can cause the joint disc to elongate and degenerate. The discs then fail to reduce when closed, causing the TMJ to become stuck in the open position (open lock). This usually happens when Opening your mouth to an extreme position, such as singing or yawning or after a long dental procedure.
1. Muscle spasms cause significant pain and limited jaw movement. This is called trismus. It usually affects one or more muscles, usually the muscles of mastication, especially the masseter and pterygium. Causes include prolonged dental surgery or Anesthetics with the mouth open for prolonged periods of time can cause bruxism and postural dysfunction.
2. Cervical posture disorders can cause jaw pain. The anterior belly of the digastric muscle extends from the point of the chin to the hyoid bone. This attachment means that when the head is extended forward, the digastric muscle will exert a rearward force on the mandible. With prolonged cervical extension Occurring in poor posture or stress-related posture, the mandibular condyle is pushed back into the retrodiscal tissue, eventually resulting in swelling pain and progressive disc degeneration.
3. Temporal tendinopathy is caused by excessive contraction of the temporalis muscle due to bruxism. There was palpable tenderness and swelling anterior to the temporalis tendon above the zygomatic arch. The temporal tendon may also be tender, where When the jaw is slightly open, it inserts onto the coronoid process palpable below the zygomatic arch.
4. The vertebrae usually fracture at the nasal symphysis or condylar neck. Often, the mandibular symphysis will fracture combined with fracture/fracture of one or both condyles. The instrument of injury may be a blow to the nose or a fall on the nose. Treatment can usually be started within a week or two after surgery to begin early stimulation of the TMJ and restore function.
There are a variety of clinical protocols used to establish a diagnosis of TMD but the Research Diagnostic Criteria for TMD (RDC/TMD) can establish mean improvement rates in diagnostic diagnosis  may also be useful on in clinical practice.
Assessment of TMD
As with all aspects of physical therapy, a thorough history should be taken. The examination should include an assessment of the patient’s posture (position of the nasal tongue and neck); palpation of the TMJ for swelling and stiffness or hypermobility of one or both TMJs; assessment of the range and normality of movement of the jaw and neck especially noting any deviation or rotation of the jaw and assessment of the patient’s bite. Also watch for signs of sleep bruxism (grinding or grinding while sleeping). Often, their sleeping partner will tell the patient if they grind their teeth or their dentist may have diagnosed excessive tooth decay or loose lips on the sides of the tongue. Other symptoms include waking up with stiff teeth waking up with muscle pain or a temporary headache or intrusion of the tongue or cheek If. the patient has OPG Xrays or MRI these can give more information about the condition of the joint and disc and if openings can be found in terms of joint motion.
Treatment of TMD
TMD is a relapsing but self-limiting condition that is often non-progressive. Non-invasive conservative treatments have been found to be effective. Physical therapy is highly effective in relieving and managing TMD even when symptoms are prolonged and severe. And the right one most physiotherapy patients will see a significant improvement in their symptoms within 3 to 6 weeks.Treatment should address the findings of the study.
- If the patient’s symptoms are severe and inflammatory, then their condition is likely to be irritating and one should proceed very slowly with the goal of first getting rid of the painful swelling and muscle tenderness there. When the pain begins to subside then begin to restore movement and alignment of the jaw. Treatment is possible including the release of soft tissue into the damaged tissue and joint fusion techniques.
- It is also important to treat any associated neck pain and headaches. Postural correction is essential and should address the position of the head, neck, shoulders, and tongue. Patients should be taught exercises to improve coordinated stability and alignment of the mandible.
- Patients with signs of bruxism should discuss with their dentist whether a bite splint is right for them. The bite splint separates the TMJ slightly to prevent compression of the TMJ when the patient bites or grinds their teeth. This can help relax the jaw muscles and reduce swelling and inflammation. There is some evidence to support the use of splinting to reduce long-term degeneration of the TMJ disc and teeth .
- Other dental problems may also need to be addressed, such as cavities that cause pain or uneven chewing, insufficient tooth height, or missing teeth.
- Patients should be taught strategies to help them manage their condition. This may include education on posture Long-term adherence to their home exercise program Good sleep habits, including sleeping positions Stress management and dietary modifications – soft food diet Acute can help reduce pain and swelling more quickly. The patient should also be taught how to reduce pressure on the TMJ by avoiding activities such as chewing on the jaw with the chin on the hand pencil while yawning with the mouth open and biting the nails while awake. They should avoid chewing chewy foods Eating gum requires a wide opening for foods such as large hamburgers and chewing on hard foods such as nuts and apples. A case report  recommends early postoperative exercises following temporomandibular joint (TMJ) ankylosis in pediatric patients and rigorous follow-up to prevent postoperative shrinkage and adhesions.
A systematic review  was published in 2015 summarizing the effectiveness of manual therapy for the signs and symptoms of TMD. It shows that cervical spine mobilization or manipulation on a mixed manual therapy protocol has considerable evidence of TMD symptom control and improvement Maximum mouth opening. Manual techniques include intraoral myofascial release and massage therapy of the masticatory muscles, atlanto-occipital joint manipulation, and upper cervical spine mobilization.
When indicated, therapists should be trained to perform cervical spine thrusts according to guidelines and standard procedures.
Results of recent clinical trials suggest that both postisometric muscle relaxation and musculofacial release can be effective supportive therapies for the restorative treatment of pain-related TMD with increased masticatory muscle tone. 
Other Causes of TMJ and Facial Pain
It is important to realize that there are other causes of pain and dysfunction in the orofacial region that need to be differentiated from TMD. Below are some of the more common ones .
1. Referred Pain – Noxious input from the trigeminal C1, C2, and C3 nerves all enter the cervical nucleus of the trigeminal nerve in the brainstem, causing referred pain. “The trigeminal nucleus is an area of the upper cervical spinal cord where sensory nerve fibers are located The descending tract of the trigeminal nerve (the caudate nucleus of the trigeminal nerve) is thought to interact with the sensory fibers of the superior cervical root. This functional convergence of the upper cervical and trigeminal sensory pathways allows bidirectional transfer of pain perception between the necks and the trigeminal sensory receptor areas of the face and head. “ This means that any part of the head and upper neck can transfer pain to any other part. It is important to carefully examine the patient’s temporomandibular joint and neck to ensure that all structures causing the condition are normal identification and processing.
2. Neuropathic Pain
- Trigeminal neuralgia (Tic Doloreaux) is characterized by severe shooting pain in the distribution of one or more of the three branches of the trigeminal nerve (cranial nerve V). It may be caused by sensitization of the trigeminal nerve or compression or impingement of the nerve. usually a support.
- Trigeminal neuritis is caused by inflammation of the trigeminal nerve.
- Complex regional pain syndrome is characterized by a constant burning pain, not necessarily on the path of a specific nerve. It is usually secondary to trauma and exacerbated by fear or anxiety. As it gets worse, skin changes and sweating may appear in the painful area. these patients Early referral to a pain specialist is needed to prevent progression of the condition.
- Bell’s palsy is a palsy of the facial nerve (cranial nerve VII). In about 70% of cases, it resolves within 6 to 8 weeks. Early treatment with prednisone can significantly shorten recovery time. If residual weakness is present, physical therapy may be needed.
- Herpes zoster (herpes zoster) usually affects the ophthalmic branch of the trigeminal nerve and presents as pain and blisters along the nerve’s path.
- Atypical Odontalgia manifests as excruciating pain with no obvious tooth etiology.
- Central Sensitization is secondary sensitization of dorsal proximal and central structures in uninjured tissue surrounding the injured area.
3. Vestibular Dysfunction can cause secondary headaches and jaw pain. The vestibular system is a complex system that includes the balance of the inner ear and central nervous system. Its main tasks are to understand the linear and angular accelerations of the head coordinate head and eye movements contribute to balance. Dysfunction of the vestibular system can cause vertigo nausea anxiety anxiety neck pain and can also cause earache and nasal congestion. Because these symptoms can resemble TMD symptoms the vestibular system should be considered as another possible cause of oral pain.
4. Parotid Stone obstruction can cause pain and inflammation of the parotid gland. This condition must be accurately diagnosed to exclude a parotid tumor. Parotid blockage may respond to effleurage type massage and more intense ultrasound.
5. Benign or Malignant Tumors should be excluded. Ankylosis contracture can be activated and painful. These secondary problems may require treatment after the tumor is managed.
6. Sinus Pain is caused by inflammation of the maxillary sinus. It is characterized by facial pain headache pain in the upper teeth and a feeling of crowded side. Sinus pain can lead to secondary cervical pain and TMJ.
7. Vascular pain or Headache
- Migraines with or without aura may be accompanied by itchy rashes that are visual or auditory sensations. It can cause secondary pressure or cervical headache. There is early evidence that treating neck dysfunction with exercise can significantly reduce its severity and frequency atrial fibrillation. Dr Ian Devlin states In the author’s experience, the cervical spine plays an important role in causing headaches. Additionally, some migraine sufferers report significant improvements in the frequency and severity of their migraines with better care of their cervical spine poor performance. In clinical practice patients report that physiotherapists for cervical spine insufficiency can reduce the frequency of migraine episodes. (11) In our practice we have found that neck stiffness relief and pain management have not only reduced but reduced the incidence of neck headaches has also helped our patients reduce their migraine headaches.
- Cluster Headaches are usually unilateral and occur in bouts lasting 30-60 minutes with 1-3 attacks per day. It is more common in men and the pain is usually worse. These headaches are usually not responsive to physio but treatment can help any cervical or secondary TMJ symptoms.
- Arterio-Venous Malformations like temporal arteritis can cause moderate to severe headache in temporal region. The pain is usually unilateral and can refer to the face and neck. It is more common in older people especially women and can be associated with polymyalgia rheumatica. These patients need immediate referral to a specialist as vision may be lost.
8. Psychogenic Pain
- Chronic Facial Pain occurs when the pain becomes chronic and psychological factors cause the pain to persist despite the complete resolution of the original injury.
- Bipolar disorder and other mental illnesses.
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