OS - TMD Flashcards
Name the origin (2) & Insertion (1) of the Masseter
origin x2
– zygomatic arch
- another origin on the underside of the zygomatic arch
insertion – angle of the mandible
Name the origin (1) & Insertion (1) of the Temporalis
Origin – temporal fossa
Insertion - Coronoid process (can extend down the anterior body of the ramus)
Name the origin (1) & Insertion (1) of the Medial Pterygoid
Origin – medial surface of lateral pterygoid plate
Insertion – medial side of the angle of the mandible (opposite to the masseter)
Name the origin (2) & Insertion (1) of the Lateral pterygoid
Origin 1 – Base of the skull
Origin 2 – lateral surface of the lateral ptergoid plate
Insertion – pterygoid fovea and some fibres extend into the capsule of the TMJ
What supplies the blood to the TMJ?
Deep auricular artery (branch of 1st part of the maxillary artery)
What supplies the innervation to the TMJ? (3)
auriculotemporal, masseteric, posterior (deep) temporal nerve
Why can patients with TMJ pain also experience discomfort in the ear?
as the auriculotemporal nerve also provides sensation to the external auditory meatus
List the 4 suprahyoid muscles (accessory MoM)
– Digastric
– Mylohyoid
– Geniohyoid
– Stylohyoid
List the 4 infrahyoid muscles (accessory MoM)
– Thyrohyoid
– Sternohyoid
– Omohyoid
– sternothyroid
How does TMJ pain arise and why?
when the articular disc slips forward the bilaminar area of the articular disc gets compressed by the condyle
- the bilaminar area has the nerve innervation
What are the causes of TMJ pain? (8)
- Myofascial pain (common)
- Disc displacement (common)
- Degenerative disease (less common)
- Chronic recurrent dislocation
- Ankylosis – condyle fused to the base of the skull (most people have a psudoankylosis)
- Hyperplasia – one condyle grows more than the other (can be bilateral but not as common)
- Neoplasia
- Infection – can result in ankylosis
What are the causes of myofacial (muscle) pain? (5)
- Inflammation secondary to parafunctional habits
- Trauma, either directly to the joint or indirectly
- Stress (muscles tense and px clench teeth)
- Psychogenic
- Occlusal abnormalities - although a restoration that is significantly “high” may cause muscle pain due to posturing
How do we identify a possible arthritic change in the TMJ?
Crepitus (crunching) during E/O TMJ assessment
What are intra-oral signs of parafucntional habits? (5)
- Cheek biting (morsicatio buccarum)
- Linea alba
- Tongue scalloping
- Occlusal non-carious tooth surface loss (toothwear)
- Hypertrophic muscles of mastication
What patients are most commonly affected by TMD (age and sex)?
Females
18-30
How do patients with TMD usually present? (5)
- Intermittent pain of several months or years duration
- Muscle / joint / ear pain, particularly on wakening
- Trismus / locking
- ‘Clicking/popping’ joint noises
- Headaches
What are other possible causes of similar symptoms? (11)
- Dental pain
- Sinusitis
- Ear pathology
- Salivary gland pathology
- Referred neck pain
- Headache
- Atypical facial pain (common in post menopausal women)
- Trigeminal neuralgia
- Angina – area of skin near the angle of the mandible is supplied by the same nerve as the heart
- Condylar fracture – hx of trauma
- Temporal arteritis
How do we treat TMD? 4 general Reversible options
Counselling
medication
Physical therapy
splints
What is involved in counselling of a TMD patient? (9)
- Reassurance
- Soft diet
- Masticate bilaterally
- No wide opening
- No chewing gum
- Don’t incise foods
- Cut food into small pieces
- Stop parafunctional habits e.g. nail biting, grinding
- Support mouth on opening e.g. yawning
What medications are used to manage TMD? (5)
- NSAIDs
- Muscle relaxants
- Tricyclic antidepressants (have muscle relaxant properties)
- Botox of masseter = prevents clenching (last resort tx)
- Steroids
What is involved in physical therapy of a TMD patient? (7)
- Physiotherapy
- Massage/heat
- Acupuncture
- Relaxation
- Ultrasound therapy (not used as much)
- TENS (Transcutaneous Electronic Nerve Stimulation)
- Hypnotherapy and CBT
What splints are used to manage a TMD patient? (2)
- Bite raising appliances
- Anterior repositioning splint e.g. wenvac or Michigan splint
How do bite raising appliances work? (2)
They stabilize the occlusion and improve the function of the masticatory muscles, thereby decreasing abnormal activity.
They also protect the teeth in cases of tooth grinding
What is the requirement for splints?
Must cover all of the teeth
What are the 2 types of disc displacement?
Anterior displacement with reduction - where the disc slips forward but can move back to its original place
Anterior displacement without reduction
How do patients with anterior disc displacement with reduction present and why?
Present with a painful clicking TMJ
- Joint clicking is due to lack of coordinated movement between the condyle and the articular disc
What is the most common cause of TMJ clicking?
anterior disc displacement with reduction
What can disc dispalcemtn progress to if they are untreated?
osteoarthritis
How do we treat disc displacement? (5)
- Counselling (education, reassurance, advice)
- Limit mouth opening
- Bite raising appliance
- Surgery occasionally may be required
- If painless, no treatment required = Reassure
List the (3) components of TMD.
- muscular initiation
- Leads to excessive mechanical loading of joint
*. underlying causes – psychological or trauma
What are the 2 underlying causes of TMD?
Psychological
trauma
What causes TMD? (4)
- Macrotrauma – one sudden incident
- Microtrauma (most common) – repetitive chronic overloading
- Occlusal factors:
- Anatomical factors – class II jaw relationship
List examples of macrotrauma that can cause TMD. (2)
physical trauma - punched etc
mouth opening for too long
List examples of microtrauma that can cause TMD. (2)
(repetitive chronic overloading)
clenching and bruxism
What occlusal factors can lead to TMD? (3)
- Deep bite (class 2)
- Occlusal disharmony e.g. high filling
- Lack of teeth
What are the superior and inferior compartments lines with? What is the function of this?
The superior and inferior compartment lined with synovial membrane
= synovial fluid = smooth movement of joint
What is the anterior section of the articualr disc attached to?
the superior head of the lateral pterygoid
What is the posterior region of the articualr disc called? what is this attached to? (2)
bilaminar zone
attached to;
posterior area of condyle
posterior area of the eminence
What is suggested if the lateral pterygoid is painful on palpation?
if painful = spasmed lateral pterygoid muscles = bruxism/clenching
what do patients with anterior disc displacement without reduction present with? (1)
Limited mouth opening
(and a history of pain and clicking)
How do we manage anterior dislocation? (6)
- Counselling (treat the cause)
- Stress management
- Pain management (pain killers and anti-inflammatory ibu 400mg 3x daily)
- Joint rest (soft food, supported yawning, chewing on both sides, avoid wide mouth opening)
- Physical therapy (warm compress and resting)
- Restoration of occlusal stability (use lower hard biting appliance)
How do lower hard bite raising appliances help anterior dislocation? (3)
- Eliminated occlusal interference
- Reduces loading on TMJ
- Prevents the join head from rotating so far posteriorly in the glenoid fossa
Apart from managing anterior dislocation what else can lower hard bite raising appliances be used for?
habit breaking
What investigations do we use for TMD? (4)
Radiographs
- 2D (OPT)
- MRI
- arthrogram (MRI with radioactive contrast medium)
Arthroscopy
What compartment is punctured during arthroscopy?
the superior compartment - penetrated from the front
What is arthroscopy used for? (7)
- Biopsy
- Diagnosis
- Disc reduction
- Lysis&lavage
- Remove foreign body/loose bodies
- Eminectomy – remove part of eminence
- Arthrocentesis = wash of the joint = increase lubrication
What are the intra & post op complications of arthroscopic procedures? (12)
- Iatrogenic scuffing
- Broken instruments
- Middle ear perforation
- Glenoid fossa perforation
- Extravasation
- Haemorrhage
- Hemarthrosis
- Damage to the trigeminal & facial nerve?
- Infection
- Disocclusion
- Laceration of EAM (External auditory meatus?)
- Perforation of tympanic membrane
What post-op instructions/management is provides after arthroscopic procedures? (5)
- Bite raising appliance
- Pain management
- Restore occlusal stability
- Physical therapy
- Joint rest (soft food, supported yawning, chewing on both sides, avoid wide mouth opening)
List the procedures that can be used if conservative measures fr TMD are ineffective? (7)
- Menisectomy = remove the disc completely
- Disc plication = move the disc to correct position
- Eminectomy = remove part of the boney eminence
- High condylar shave
- Condylotomy
- Condylectomy
- Reconstructive procedures
What are the indications for TMJ reconstruction? (3)
Joint destruction from;
- Trauma
- Infection
- Tumours
- Previos surgery
- Radiation
- Ankylosis
- Developmental deformity
Define class 1 TMJ ankylosis.
flattened deformity of the condyle, little joint space and extensive fibrous adhesions
Define class 2 TMJ ankylosis.
boney fusion at the outer edge of the articular surface
Define class 3 TMJ ankylosis.
marked fusion bone between upper part of ramus of the mandible and the zygomatic arch
Define class 4 TMJ ankylosis.
entire joint replaced by a mass of bone
