Chronic TMD, Diagnosis and Management

Question 1

What is the most common chronic primary orofacial pain?

Answer 1

TMJ pain (facial arthromyalgia)

Question 2

What is facial arthromyalgia?

Answer 2

TMJ pain

Question 3

Which conditions come under the category of chronic primary orofacial pain?

Answer 3

TMJ pain

Atypical facial pain

Burning mouth syndrome

Atypical odontalgia

Question 4

According to the ICD-11 classification, what common characteristics do the conditions that come under the category of chronic primary orofacial pain have?

Answer 4

Persistent pain >3 months

Affected patients have significant functional and emotional impairment (not just physically impaired but often also mentally impaired).

A lot of these patients will have associated depression, anxiety, increased frustration/anger which interferes with their day to day activities

These common characteristics are suggestive of common underlying mechanisms between these conditions (which is why they’re clustered together)

Question 5

Define pain

Answer 5

An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage (in the absence of disease)

Question 6

Describe the historic understanding of pain and the revised understanding of pain

Answer 6

In the past, pain was known as a purely a sensory experience. In that it was picked up as noxious stimuli by the body to elicit a protective response from the body that would result in the patient moving away from the noxious stimuli.

Now it is understood that pain is modulated by prior experiences, expectations, anxiety, mood, genetics, central/peripheral sensitisation, gate control theory

Question 7

How can we modulate the pain response using the gate control theory?

Answer 7

The pain response can be blocked by stimulating the gamma receptors. This is why when we massage or rub an area of pain, the pain momentarily disappears.

Descending inhibition can also inhibit the pain response. These are the psychological receptors or the limbic system. This is why when we distract ourself, we potentially feel less pain (as we’re blocking the pain gate)

Question 8

TMJ pain is an example of nociplastic pain. What does this mean?

Answer 8

Pain that arises from altered nociception despite no clear evidence of actual or threatened tissue damage, causing the activation of peripheral nociceptors

OR evidence for disease or lesion of the somatosensory system causing the pain

Essentially pain felt in the absence of disease

(Nociceptors are the receptors that pick up on pain/noxious stimuli)

Question 9

What model should the dentist use to make a TMJ diagnosis?

Answer 9

Biopsychosocial model

Axis 1 - TMJ signs and symptoms

Axis - Psychosocial symptoms

Question 10

A patient presents with TMJ symptoms, how would approach examination?

Answer 10

Palpation of the lateral poles of the TMJ with the index finger. Ask whether the patient feels any pain on palpation

Assess for any abnormal sounds (clicking/crepitus) and pain on opening and closing of the mouth

Assess the patient’s range of motions- Maximum range of opening that is considered normal - 4cm for males, 3.5cm for females. Ascertain whether the patient is opening their mouth normally or whether there is restricted mouth opening.
Assess whether the jaw deviates on opening. Ascertain whether the deviation sustained or transient.

Assess the MoM for any tenderness on palpation-
When palpating the masseter, we need to palpate the origin (originates from the zygomatic arch) and the insertion (into the lower border of the mandible intra-orally)
Can opt to palpate the trapezius and sternomastoid muscles (muscles in the neck) to see if the pain is extending beyond the MoM.

Assess the function/strength of the pterygoid muscles-
Ask the patient to bite together in occlusion, place resistance under the patient’s chin and then ask the patient to attempt opening their mouth / sliding their jaw from left to right.

Once complete, assess for some red flags that would indicate trismus-
Mouth opening less than 15mm/1.5cm and getting progressively worse
Neuralgia, sharp, shooting electric pain (non-myogenic origin)
Absence of a history of clicking
Swollen lymph glands
Suspicious IO soft tissue lesions

Only takes one red flag sign to warrant referral to OMFS for assessment

Question 11

What condition can present like TMJ pain? How would this condition be managed?

Answer 11

Giant cell arteritis can also cause severe pain in the temples, much like TMJ pain

Requires high dose of steroids immediately to prevent blindness

Question 12

List the red flags that would indicate trismus. If any of these are detected, what should you do?

Answer 12

Mouth opening less than 15mm/1.5cm and getting progressively worse

Neuralgia, sharp, shooting electric pain (non-myogenic origin)

Absence of a history of clicking

Swollen lymph glands

Suspicious IO soft tissue lesions

Refer to OMFS unit for assessment

Question 13

During an E/O of a patient presenting with TMJ symptoms, you notice a sustained deviation of the jaw on opening. What does a sustained deviation look like? Why is this concerning?

Answer 13

On opening, the jaw deviates and does not return to its central position, staying in the deviated position instead

Could indicate a lesion within the joint (osteochondroma of the joint for example)

Question 14

What does clicking of the TMJ indicate?

Answer 14

It indicates an intra-articular joint disorder

Specifically, it means the lateral pterygoid muscle is tense, causing the articular disc to be displaced in a more anterior position at rest.

On opening, the movement of this anteriorly displaced articular disc results in clicking.

Question 15

What could crepitus of the joints indicate?

Answer 15

Osteoarthritis

OR

Rheumatoid arthritis

Affecting the TMJ

Question 16

What should a structured history of a patient who attends your clinic with TMJ symptoms look like?

Answer 16

Brief C/O-
Site, descriptors, duration, pattern of pain

Medical history-
Anti-depressants, anti-anxiety medication?

Psychosocial history-
Any underlying anxiety or depression?

Co-morbidites-
Any other areas affected by chronic pain?

Detailed SOCRATES-
Site- TMJ, MoM, within the ear

Onset- sudden or gradual

Character- aching, deep, continuous pain with potential for acute flare ups. May be episodic (as some patients will clench and grind their teeth during various levels of stress)

Radiation- to ear, angle of jaw, temple, teeth, head (where temporalis is involved)

Associations and alleviating factors- rest, analgesia (include anti-inflammatories, paracetamol is not as effective because the pain is muscular),

Timing- can worsen throughout the day or night but often a continuous pain. Patients who clench their teeth at night will complain of more pain in the morning and vice versa

Exacerbating- dynamic movements of the jaw, chewing, yawning, prolonged mouth opening

Severity- variable

Question 17

Describe the pathophysiology of TMD

Answer 17

TMDs involve a 3-way system comprising the-
Teeth

Muscles (MoM, neck muscles, digastric and sternomastoid muscles)

Joint

As we clench and grind, the MoM i.e., masseter, temporalis, medial pterygoid and lateral pterygoid (which are attached in front of the disc) and the neck muscles etc., get activated. This is how TMJ disorders arise.

Question 18

What special investigations can be taken for a patient presenting with TMJ symptoms?

Answer 18

Dental radiography (to include potential dental causes)

Question 19

List the different diagnoses of TMJ disorders with a brief description for each.

Answer 19

Intra-articular joint disorders (disc displacement, with or without clicking and with or without locking). Indicated by clicking sounds within the joint

Degenerative joint disorders (osteoarthritis or rheumatoid arthritis). Indicated by crepitus sounds within the joint

Pain related TMD and headache (various forms including myalgia, myofascial pain, headache attributed to TMD, arthralgia)

Question 20

Define myalgia

Answer 20

A pain related TMD, affecting the MoM

Question 21

Define myofascial pain

Answer 21

A pain related TMD,

Pain extends beyond MoM, radiating to the neck and head

Question 22

Define arthralgia

Answer 22

Pain related TMD

Unexplained pain in the joint (joint feels sore on palpation/opening but there are no associated joint sounds or pain in the MoM)

Question 23

How does clicking arise in the TMJ?

Answer 23

Arises due to the presence of an intra-articular joint disorder.

At rest, the lateral pterygoid muscle tenses, causing the articular disc to be displaced in a more anterior position

On opening, the movement of this anteriorly displaced articular disc results in clicking.

Question 24

What is a PHQ-9 form and what relevance does it for a patient presenting with TMJ symptoms?

Answer 24

Used to ascertain whether a patient has psychosocial factors (anxiety or depression or severe distress) that may be the cause of the symptoms

Question 25

TMJ pain is often misdiagnosed for other conditions. List some

Answer 25

Otalgia (due to the overlap of pain experience near the ears, where some of the involved muscles are located. Patients often mis-referred by GPS to ENT surgeons)

Toothache (upper molars, next to the upper 6s, we have the temporalis attachment)

Persistent idiopathic facial pain (PDAP)

Acute and chronic maxillary sinusitis

Question 26

How do we distinguish between sinus pain and TMJ pain?

Answer 26

Get the patient to lean forward, if the pain worsens (shooting pain), it is likely sinusitis

Question 27

Describe the relationship between Chronic primary orofacial pain, an altered bite and anxiety

Answer 27

Whilst altered bite can be associated with chronic primary orofacial and TMD pain, the association is often confounded by anxiety.

If a patient is anxious or stressed, they often feel their bite is altered.

When the masseter muscle gets tense, it may alter the position of the mandible slightly which may make the patient feel like they have an altered bite. The masseter and temporalis are important in closing the jaw. If these muscles are tensed, it may impair the patient’s ability to close.

Question 28

What is the first line of treatment for TMJ symptoms?

Answer 28

Guided self-management

Includes education + physical self-regulation (sleeping on the back etc.) + psychosocial self-regulation (low intensity CBT, challenging the negative thoughts around the pain etc.)

Question 29

What does guided self-management involve?

Answer 29

Collaborative patient-centred approach.

Involves educating the patient about the condition and its management.

Involves understanding the issue from the patient’s perspective using impact sheets to determine how the pain affects day to day life.

Involves goal setting using physical and psychosocial self-regulation, asking the patient what they want to achieve through management e.g. prevent sleep interference, stop jaw feeling so firm and rigid etc.

Involves making the patient independent in self-management so that they can continue to manage their pain (relapse prevention)

Once achieved, patients can be discharged

Question 30

List the 4 steps of guided self-management

Answer 30

Step 1-
Diagnosis, educating the patient about their condition (present diagram of jaw anatomy, inform them of the Gate Control Theory). Important that the patient understands the basis of their pain so that they can perceive self-management as a valid solution. Give patients the manual for management of chronic primary orofacial pain

Step 2-
Ascertaining the impact of the pain on the patient’s day to day life using impact sheets (how does the pain impact the patient’s thoughts, feelings and behaviours?)

Step 3-
Identifying methods of physical and psychosocial self-regulation to address the problems caused by the patient’s symptoms (problem centred rather than diagnosis led management). Goal setting to manage the impact of the condition. These interventions can be divided into 3 key groups (autonomic e.g., sleep hygiene, behavioural e.g., sleeping on the back, massaging MoM, heat/cold packs, cognitive e.g., CBT, restructuring of negative thoughts surrounding the pain, increasing her awareness of parafunction)

Step 4-
Relapse prevention, making the patient independent in self-management and able to continue managing their pain day to day

Question 31

It is understood that a diagnose, treat and cure model cannot be used to effectively manage TMD patients. Describe the model that works more effectively for the pain these patients experience.

Answer 31

Diagnose, establish impact, set target goals, relapse prevention and discharge

OR

Diagnose, identify habits (parafunction) / pain triggers (anxiety/psychological distress), reversal of habits / avoidance of triggers (divert patient attention from anxiety via stress ball etc.), relapse prevention and discharge

Question 32

Describe some methods of physical self-regulation to manage TMJ pain

Answer 32

Soft diet

Avoid activities that involve wide opening (yawning) until pain reduction

Techniques to stop patients from opening their mouth when they’re yawning e.g., advising patients to place their chin onto their neck

Techniques to reverse clenching and grinding habits e.g., sleeping on the back, regularly massaging the masseter muscle from origin to insertion with 4 fingers (allows the jaw to drop, preventing the teeth from being in contact)

Massage of muscles, heat/cold packs (this blocks the pain fibres by stimulating the thermoreceptors/mechanoreceptors to divert attention from pain to hot/cold or pressure stimuli

Posture control (sleeping on the back)

Question 33

A 54 year old patient presents with pain in the UR6 that has been ongoing for 5 years. The tooth has been crowned and RCT’d. On dental imaging, there is no pathology to indicate the RCT has failed. On further inquiry, the patient states the pain is a dull, throbbing ache that travels to the head, neck and ear. You notice no suspicious swellings or draining sinuses. What is the likely diagnosis?

Answer 33

Myofascial pain

Question 34

List the aspects of day to day life that an impact sheet may include

Answer 34

Impact on home (housework, cooking)

Impact on work

Impact on relationships (family/others)

Impact on social activities

Impact on personal activities

Question 35

Describe the vicious circle of pain that dentists should consider for TMD patients

Answer 35

How does the pain impact the patients feeling, thoughts and behaviours.

It is thought that a negative change in one of these factors, will have an impact on the other 2.

Question 36

Why is a stabilisation splint not considered an effective solution for TMJ symptoms?

Answer 36

Not evidence based, only to be used as an interim solution.

If a splint is provided, the patient will need to be monitored as this is not a permanent solution and can actually make the pain worse (the splint provides something for the patients to clench on, activating their MoM but ideally, the teeth need to remain apart rather than together to prevent TMDs).