TEMPOROMANDIBULAR JOINT DISORDERS
Temporomandibular joint (TMJ) that is present on each side of your lower jaw in front of the ear, helps in gliding and rotational movement of the lower jaw. This joint like any other joints are affected with disorders or lesion or pathologies or secondary to fractures or trauma. Hereby we enlist the types of disorders encountered with this joint
Subcategories of TMJ Disorders (TMDs)
- Myofascial pain disorder
- TMJ disc interference disorders
- TMJ degenerative diseases
MYOFASCIAL PAIN DISORDER
Etiopathogenesis and Proposed Mechanisms
There is no exact mechanism or single source of reason for the case but a multifactorial origin might cause such disorder. The following three factors are meant to be the major causes:
- Continuous source of input leading to deep pain
- Heightened emotional stress
- Sleep disturbances
Questions concerning pain and restricted jaw movements and TMJ sounds
- Visual examination of the head and neck.
- Palpation of the head and neck—This includes palpation of the individual masticatory muscles for tenderness
- Listening to TMJ sounds and joint palpation
- Mandibular movements—For range of motion an deviation.
- Radiographs and other imaging techniques—An OPG may be easily available in most clinical set ups. Dental CBCTs offers reasonable hard tissue detailing, articular surface erosions and joint space dimensions. MRIs for imaging soft tissues such as the disc and joint ligaments
- General oral examination.
Role of Parafunctional Habits
Bruxism
- Bruxism is as an oral habit of involuntary rhythmic non-functional clenching of the lower jaw “tooth grinding neurosis”.
- Associated with REM, commonly seen in patients with high anxiety or increased depressive symptoms.
- This sustained muscle contraction leads to non-serous inflammatory reaction in masticatory muscles, subsequent fatigue and pain.
- Signs of bruxism:
- Attrition of teeth
- Scalloping of the tongue
- Cheek ridging—linea alba
Clinical Signs of MPDS
- Pain in TMJ region
- Clicking/popping noise
- Restriction of mouth opening
- Deviation of lower jaw midline to the affected side on mouth opening before clicking
- Restricted lateral jaw movements to the contralateral side
- Unrestricted lateral jaw movements to the affected side
Central and peripheral causes of MPDS
Central causes
- Stress Adverse
- Anxiety
- Depression
Peripheral causes
- Adverse postural issues
- Repetitive localised strain in the form of occlusal parafunction
Causes of clicking
- Disc displacement with reduction
- Hypermobility of the condyle
- Loose intra-articular bodies like arthroliths, intra-articular fracture fragments of the articular surface
Thickening of the soft tissue on the slope of articular eminence
Management of MPDS
Muscle Exercises
Muscle exercises are the most effective for muscle rehabilitation. Active muscle stretching combined with passive exercises diminishes the sensitivity of trigger points. Postural exercises reduce trigger point reactivation, while strengthening exercises serve to enhance circulation and suppleness of the muscles. Determination of the muscular range of motion is the preliminary requirement prior to prescribing physiotherapy
Correctional exercises :
1. Placement of the tip of the tongue on the roof of the mouth with the teeth parted.
2. Instruction in proper posture for daily activities like sitting, standing and lifting of objects.
3. Encourage sleeping on the side or back. This is effective for patients who complain of muscle stiffness upon awakening.
4. Incorporate a form of aerobic exercise into the daily routine to improve mood, circulation, strength and muscle endurance
Muscle Treatments
Splints Used in the Management of MPDS
Types of splint:
- Permissive/muscle deprogrammers, e.g. stabilization splints, gnathological splint
- Non-permissive/directive, e.g. anterior repositioning splint
PHASES & ITS MANAGEMENT
INTERNAL DERRANGEMENTS
The most common presenting complaints in patients with TMJ internal derangement include:
- Pain
- Joint noises (click or crepitation)
- Loss of function
- Occasionally a change in occlusion
Other factors and details prior to treatment attempts includes :
- Location
- Radiation
- Severity
- Timing (intermittent or constant)
- Duration and frequency of episodes
- Exacerbating factors
- Relieving factors
- Associated symptoms (headache, tinnitus, etc.)
General treatment goals for Treatment for internal derangement :
- Decrease joint overload
- Decrease pain
- Reduce inflammation
- Improvement in the range of motion
- Restore function
- Causative factors to be identified and controlled
Nonsurgical options include:
- Patient education
- Soft diet
- Occlusal appliance/orthotic devices
- Parafunctional habit awareness
- Biofeedback
- Nonsteroidal anti-inflammatory medication
- Muscle relaxants
- Botulinum toxin
- Physical therapy
SURGICAL MANAGEMENTS :
- Arthroscopy & Arthrocentesis
- Disc repositioning
- Arthroscopic
- Arthrotomy
- Discectomy & Arthroplasty
- Joint replacement
- Alloplastic
- Autogenous
Disc replacement options
Alloplastic
- Methyl methacrylate
- Silastic
- Proplast-Teflon
- Fossa prosthesis
Allogenic
- Dura (cryopreserved)
- Cartilage (lyophilized, freeze-dried)
Autogenous
- Temporalis muscle/fascia
- Ear/rib cartilage
- Dermis skin grafts
- Abdominal fat
Xenograft
- Bovine collagen/cartilage
Temporomandibular Joint Dislocation
Dislocation refers to a condition in which condyle (joint) is displaced out of the socket and traverses in front of the bony projection and the patient cannot bring back to its normal position leaving the jaw open (locked jaw).
Subluxation is the condition in which the dislocated condyle can be reduced back into the normal position by patient themselves, without any professional assistance
Classification of Dislocation
Based on duration of displacement
- Acute dislocation
- Habitual dislocation/subluxation
- Chronic recurrent dislocation
- Long-standing/chronic protracted dislocation
Based on direction of displacement
- Anterior
- Posterior
- Medial
- Lateral
- Superior
Based on side of displacement
- Unilateral
- Bilateral
Etiology of dislocation
- Trauma
- Medical and surgical procedures
- Dental procedures which require wide mouth opening for prolonged time
- Intubation procedures, gastrointestinal endoscopy, laryngoscopy/bronchoscopy
- ENT procedures
- Spontaneous Laughing
- Yawning
- Biting
- Vomiting
- Singing
- Epileptic seizures
- Poorly grooved fossa, shallow/steep articular eminence, laxity of ligaments and capsule for more prone for dislocation
- Systemic disorders Ehlers-Danlos disease, Marfan’s syndrome, Huntington disease,
- Medications: Antipsychiatric, Antiemetic
- Occlusal conditions: Edentulous posterior region
Clinical Features of Dislocation
The classical clinical features of dislocation are:
- Pain in the preauricular and surrounding region.
- Preauricular depression/hollowing.
- Protruding chin.
- Inability to close mouth.
- Drooling of saliva.
- Inability to speak, swallow, or masticate.
Investigations
- Orthopantomogram (OPG) (open and closed)
Commonly used screening. Morphology of joint-condyle, fossa, and joint space can be evaluated. Open mouth OPG shows the position of the condyle in relation to the articular eminence.
- TMJ tomogram
Open and closed mouth TMJ images.
- Computed tomography(CT)
Morphology of osseous TMJ components— condyle, articular eminence and the glenoid fossa—are better assessed with CT.
- Cone beam computed tomography CBCT
condylar height, width, length, inclination of articular eminence.
- Magnetic resonance imaging (MRI)
soft tissue morphology, particularly disc shape, displacement, and effusion
- Electromyography (EMG)
activity of the muscles which may be hypoactive, normoactive, or hyperactive.
- Ultrasonography (USG)
Thickness and length of the muscles.
Management of Acute Dislocation
- Conventional technique—Hippocratic/Nelaton’s method
- Wrist pivot technique
- Extraoral technique
- Gag reflex
Management of Chronic Recurrent Dislocation/ Subluxation
Conservative
- Physiotherapy
- Intermaxillary fixation
- Chin straps
- Barton’s bandage
- Kinesio taping
Minimally invasive
- Injection of sclerosing agents
- Autologous blood injection
- Prolotherapy
- Botulinum toxin injection
Surgical procedures
- 1. Capsular tightening procedure
(a) Capsulorrhaphy
- Creation of mechanical obstacle
(a) Dautrey’s procedure
(b) Glenotemporal osteotomy
- Removal of mechanical obstacle
(a) Eminectomy
(b) Condylectomy
- Creation of new muscular balance
(a) Temporalis scarification
(b) Lateral pterygoid myotomy
(c) Pterygoid dysjunction
Management of Long Standing Dislocation
Conservative
- Manual reduction
- Continuous elastic traction using bite block
- Indirect reduction
(a) Using a wire passing
(b) Using a hook
Surgical procedures
- Joint surgerieds
(a) Condylotomy, condylectomy
(b) Myotomy
(c) Joint prostheses
- Procedures not involving the joint
(a) bilateral Sagittal split osteotomy
(b) Vertical ramus osteotomy of single side
(c) Inverted L osteotomy of single side of ramus
(d) Midline mandibulotomy
Temporomandibular Joint Ankylosis
Temporomandibular joint (TMJ) ankylosis is defined as bony or fibrous adhesion of the anatomic joint components accompanied by limitation of mouth opening, causing difficulty in mastication, speech, and oral hygiene. This may also influence symmetry of the facial skeleton, especially in cases which occur when patient is still in the growth phase
Investigations
- Detailed history, complete clinical examination, professional photographs, for documenting the:
- Age of onset of ankylosis
- Type, duration, and extent of ankylosis
- Type of joint injury or infection
- Maximal interincisal opening
- Dental characteristics and occlusion
- Type of facial deformity
- Previous surgery
- Routine hemogram and pre-op major investigations
- Radiological examinations for evaluation of extent of ankylotic mass, discrepancy of jaws, and treatment planning
(a) Orthopantomogram:
(i) Decreased joint space
(ii) Absence/presence of normal condylar and coronoid anatomy
(iii) Prominent antegonial notch
(iv) Markings for osteotomy cuts (for distraction)
(b) PA cephalogram:
(i) Chin deviation
(ii) Occlusal cant
(c) Lateral cephalogram:
(i) Ramal length
(ii) Corpus length
(iii) Pharyngeal airway space (PAS)
(d) Facial CT scan:
(i) Three-dimensional anatomy of bony morphology
(ii) Any anatomical measurements as and when required, e.g., size of ankylotic mass, location of ligula, airway space volume, etc.
(e) CT Angiography may be required to assess the relationship of internal maxillary artery to the ankylotic mass. There are chances of the vessel being inside the bone, especially in re-ankylosis cases.
- Assessment of OSA may be done using Epworth sleepiness scale, Pittsburgh sleep quality index, and polysomnography (PSG) for:
(a) Apneic-hypopneic index (AHI)
(b) Nocturnal desaturation episodes
(c) Average respiratory disturbance index
(d) Average lowest arterial oxygen saturation
- 3D stereolithographic models printed, with the help of CT scan, may be used in treatment planning. Patient-specific surgical guides aid planning, precise control during operation, and thus more foreseeable treatment results.
TREATMENT PLAN AND MANAGEMENT : Executed based of the age of the patient, involvement of the joint, the severity and the functional disturbances
