Temporomandibular Joint Disorders (TMD) are most commonly the result and cause of malocclusion of teeth (badly arranged teeth). The chewing muscles (masticatory), which position and connect the mandible to the skull, should be the focal point of correct occlusion. Occlusion(bite) is maintained by the activities of these masticatory muscles which are controlled by neural integration of the feedback from peripheral proprioceptors and the reflex mechanism from the Central nervous system. This is science.
Symptoms of Temporomandibular Joint Disorders
- Clenching and grinding
- Pain or tenderness in your face
- Snoring and disturbed sleep
- Pain around neck and shoulders
- Popping sound in ears
- Pain on chewing
In addition to the above symptoms you may also face sleep apnea, hearing problems, restless legs, toothaches, dizziness, overall lethargy etc.
If you have any of the above symptoms, it may be a sign of TMD!!
WHAT IS OBSTRUCTIVE SLEEP APNEA (OSA)?
Lifestyle diseases are on the rise in the world especially in India where the proportion of the middle class is increasing manifold. Hypertension, cardiovascular diseases, diabetes, increased lipids is just to name a few. We hear about sudden cardiac arrests and related deaths, irrespective of age and sex, very regularly nowadays; especially during sleep. It is also common to hear that these deaths are labelled as myocardial infarctions and that it is unfortunate! But, do you know that 75% of these “unfortunate” deaths could have been avoided if only he/she was diagnosed for a killer disease known as “OBSTRUCTIVE SLEEP APNEA (OSA)”. It is very commonly treated by sleep medicine specialists in the west in close collaboration with physicians and dentists. But here, in India, even the sleep physicians are finding it tough to get through to the patient due to the lack of awareness.
Now, what is OSA?
It is a self-explanatory term which describes the condition wherein the person is not able to breathe normally at sleep due to an obstruction in the airway. The upper airway occlusions comprises of the naso-pharyngeal blockages like polyps, adenoids or deviated septum; oro-pharyngeal occlusions like macroglossia or posterior mandibular positioning; velo-epiglotto-pharyngeal occlusions like tonsillitis or a long uvula; or even a large neck circumference (increased BMI). All these press upon the airway, leaving the person gasping for air to breathe. The tongue (the genioglossus attached to the mandible) is almost always the biggest troublemaker.
During sleep, when our whole body is at rest, the mandible falls backward pulling the tongue along with it, thus obstructing the airway space. This results in lesser oxygen entering the body during sleep. Hence, the heart would need to pump out oxygen-rich blood at a higher pressure. Since, the oxygen intake is at a lower level, the resultant hypercapnia (increase in blood-CO2 level) sends signals to the brain which then asks the person to bring the tongue forward; which then drags the mandible upwards along with it; ending in clenching/grinding, waking up the patient (or a simple toss and turn) to start the breathing cycle again; thus saving him/her. Long term apnea leads to a weak heart killing the person, eventually, during sleep.Sleep bruxism is now considered to be a physiological consequence of OSA as per new research. A clenching/grinding event occurs when an oxygen desaturation episode occurs.
DIAGNOSIS OF TMD AND OSA
As the signs and symptoms of TMD match various other disorders, patient evaluation starts with thorough oral and physical examination. The dentist also takes complete health history of the patient.
Dentist does the following oral examination in case of any suspicion of TMD:
Check jaw for pain or tenderness by palpating extra auricular area
Listen for clicks, pops, or grating sounds while patient moves the jaw
Evaluate the proper working of the jaw by placing small finger intra-auricular
Observe the range of motion in jaw
Extra –oral for facial symmetry, postural imbalances, nasal deviation, etc
Intra-oral for malocclusions, missing teeth, faulty dentures, tongue position, etc
After thorough oral examination, following diagnostic tests may be done for confirmed diagnosis of TMD:
Blood tests to rule out possible medical conditions as a cause of the problem.
X-rays and Panoramic Radiographs of jaws, temporomandibular joints and teeth -
1. Lateral Cephalogram to look for airway patency, jaw placement and measure of lordosis
2. OPG to look for the status of teeth
3. TMJ View (left and right, open and close)
MRI to find if the TMJ disc is in the proper position during jaw movement as it provides images of the disc as well as the muscles and other soft tissues surrounding the joint.
A CBCT scan to view the bony detail of the joint in case screening radiograph of the TM joint shows some bony changes
TMJ arthroscopy to view the TMJ and determine a diagnosis although its now not as used with NMD due to its sclerotic consequences
Scintigraphy (Bone scan) to find out whether a pathologic process is in an active or inactive state.
Patient may be referred a physiotherapist or ENT surgeon to rid the patient of any other ascending or descending causes of TMD.
Diagnosis of Obstructive sleep apnea
Diagnosis of OSA involves thorough physical examination and complete history taking of the patient. Physical examination includes:
Examination of the back of throat, mouth and nose for extra tissue or abnormalities
Measurement of the neck and waist circumference, weight imbalance
3D CT of Airway or Volumetric CT
Blood pressure measurement
All prospective OSA patients need to undergo a sleep study at night, where they need to sleep one night in a hospital or even at home with an ambulatory sleep study machine. The most important reading from this sleep report would be the AHI (apnoea-hypopnea index) and the number of desaturations.
In most of the cases, the doctor prefers to talk to the sleeping partner of the person to find out if the condition is OSA.
Patient may need to undergo Sleep study or Polysomnography (sleep study report) to confirm the diagnosis of OSA. Patient needs to spend a night in the sleep centre for sleep study. It involves overnight monitoring of the breathing and other body functions of the patient including:
Blood oxygen levels
Electrical activity of the brain
WHAT IS NEUROMUSCULAR DENTISTRY?
How long have few of our patients been suffering from headaches? For how many years have they been popping those anti migraine pills? Does their snoring disturb those sleeping with them or even those in the next room? The field of medicine has always involved reasoning. For every problem that patients suffer from - the headaches (HA)/neck aches(NA)/migraine/snoring/interrupted sleep/excessive daytime sleepiness - there is a cause. Treat the cause; instead of being dependent on medicines for a lifetime. Once the cause is removed, so is their problem. 80% of all uncured headaches/neck aches/disturbed sleep is caused due to a simple malpositioning of your lower jaw, the mandible. The malpositioning happens as a result of erratic chewing habits, such as single side eating (due to missing teeth on the other side), failed prostheses, wrong breathing habits or even failed orthodontic treatment. These would lead to an error in the way our lower teeth are supposed to occlude with the upper teeth. This causes a shift in the mandibular position as the body has to find a solution so that the person can chew his food. This faulty positioning, changes the way the mandible articulates with the skull; more often than not, pushing it upwards and backwards. The articulation or joint is known as THE TEMPOROMANDIBULAR JOINT(TMJ) AND THE ERROR IN IT IS CALLED TEMPOROMANDIBULAR JOINT DISORDER (TMJD OR TMD). Through the sheath of this joint travel important nerves that supply a variety of muscles in and around the head and neck region. Hence, any constant stimulation of these nerves keeps those muscles in a hyperactive state for long periods, thus causing pain in the area. This neuromuscular pain ends up as the HA/NA that patients suffer.
TMD is treated most successfully by NEUROMUSCULAR MEDICINE/DENTISTRY(NMD). NMD is done in 2 phases. The first phase is splint therapy. A lower splint is constructed by filling the space between the teeth that is created by the use of a TENS device that relaxes your facial muscles and then the use of a highly sophisticated mandibular tracking device that determines the actual position of your mandible. Once the symptoms are nil, normally after a period of 5-6 months, the splint is removed and the 2nd phase is started, wherein the space is permanently closed by either crown/bridges or orthodontic therapy.
In summary, NMD is the science of occlusion encompassing not only the teeth but the objective evaluation of the status and function of the jaw muscles and joints – before, during and after treatment – to achieve the optimal result.
The treatment is basically getting rid of these airway occlusions. The patient, at first needs to be cleared by the ENT, for any nasal/throat obstructions. We now need to keep the tongue forward during sleep with adjustable custom made oral appliances. These are constructed by recording the correct bite-registration; which is normally 30% of maximum opening and 70% of maximum mandibular protrusion also checking for adequate muscle facilitation. This helps in keeping the mandible and the attached tongue in a forward position opening up the airway. The C-PAP also works in an almost similar manner by passing positive air pressure through the nostrils, thus opening the airway. However, due to its cumbersome nature, more and more patients are now opting for oral appliances.
Common sleep problems like snoring, night clenching, sleep bruxism, sleep restlessness, restless leg syndrome, sleep talking, somnambulism, disturbed sleep and excessive daytime sleepiness need to be identified. These are things that are seen in almost everyone but need to be tackled seriously.
So, its time to think neuromuscular and promote treatments with the TENS and K7 therapy for management of TMD issues.