TMJ Flashcards
Opening: Normal vs functional vs excessive opening
- Normal: 40-45mm males; 45-50mm females
- Functional: 35mm (3fingers/2knuckles dominant) or 4 fingers/3knuckles nondominant)
- Excessive:>55mm
Arthrokinematics of opening:
- posterior rotation predominates in 1st 1/2 motion (~11-25mm)–> inferior cavity
- Anterior translation predominates in last 1/2 motion (>25mm) opening–>superior cavity
**pattern reverses with closing
Lateral deviation: normal range
1/4 opening; ~10mm
Lateral deviation: arthrokinematcs
Rotation/spinning of I/L condyle and horizontal translation of C/L condyles
Protrusion and retrusion norms
P: 6-9mm
R: 3 mm
Joint capsule properties and areas of looseness/tightness
- Highly vascular and innervated
- Firm medially
- loose anterior/posterior to allow movement
superior vs inferior cavity; what goes on here and what divides them?
disk divides joint into superior and inferior cavities
- -rotation occurs in INFERIOR cavity
- -translation occurs in SUPERIOR cavities
TMJ innervation
Mandibular division of trigeminal nerve (anterior and medial TMJ = deep and masseteric branches, posterior and lateral = auriculotemporal nerve
Muscles of elevation:
- Masseter
- Temporalis
- medial Pterygoid
- superior fibers of lateral pterygoid to stabilize disk
Muscles of depression:
- inferior lateral ptrygoid
- digastric
- infrahyoids
Muscles of protrusion
- superficial masseter
- medial pterygoid
- lateral pterygoid
Muscles of retrusion:
- deep masseter
2, temporalis - suprahyoid
Muscles of lateral deviation:
- I/L temporalis
- I/L masseter
- C/L pterygoids
ADDwR
- Disc displaced anterior with mouth closed,
- opening reduces disk back ontop of C.head (1st click)
- @ beginning of closing disk-condyle complex translates together posteriorly
- @ end of closing disc displaces anteriorly again (2nd click) **due to excessive contraction of superior head of Lat. pterygoid and decreased elasticity of posterior striatum fibers
ADDwoR
- no clicks, disks permanently stays in front of condyle
- opening may be limited (closed lock)
Posterior disc displacement (PDD)
- rare, can be due to prolonged wide opening or stretch of lateral pterygoids
- closing limited (open lock)
Dislocation:
unable to close, can be due to hypermobility, trauma, genetic (EX: ehlers-danlos)
Subluxation:
excessive lateral protrusion of involved condyle with opening
Ankylosis:
Restricted ROM/opening limited with deviation to involved side (may be secondary to polyarthritis, inflammation, etc)
Myofascial pain: s/sx, common trigger points
-Masseter TrP: refer to lower teeth
-Temporalis TrP: refer to upper teeth
S/Sx: TrP = hallmark; HA, facial pain, jaw/neck pain, tinnitus, earache, dizziness, swallowing difficulty, TMJ noises
Myositis
Acute inflammation; palpable tenderness with limited opening
Trismus
spasm in masseter muscle
- Hx is major clue
- Opening <25mm typically
- Overuse (chew hard food/gum), dental procedure (overstretch)
Dystonia:
CNS dysfunction
-Need botox or medical Tx
Arthrides
inflammation of joint (EX OA); crepitus, limited and painful ROM
**With RA and psoriatic arthritis, joint protection and inflammation control are of primary importance
Capsulitis:
“C” curve with deflection and protrusion to involved side
-presents similarly to synovitis
Why can you get ear Sx/cervical Sx with TMJ disorder
- Trigeminocervical Nucleus (neuron pool in basal ganglia) and Auriculotemporal Nerve
- synapse of CNV, VII, IX, X, XI and C1-C3 spinal nerves
Trigeminal neuralgia:
electric/stabbing pain at V2-3 (trigeminal); intermittent and abates in seconds/minutes
Poster Herpetic Neuralgia:
CONSTANT electric/stabbing pain at V1 (trigeminal)
Temporal arthritis:
subacute inflammation
- severe U/L or B HA
- jaw claudication with pain/stiffness
- *MUST eval opthamologically due to risk of vision loss–refer back to MD in this case**
Atypical Odontalgia
- Phantom Tooth pain
- Constant burning/pressure like pain after endodontic/dental distraction procedures due to disruption of neural pathways to alveolar or pulp
Miniere’s disease:
Combo of vertigo, tinnitus, aural fullness
–studies show benefit with concurrent Tx to TMJ and C-spine regions in PT
C curve vs S curve
C curve: capsular; deviates to involved side; If capsular tightness will demonstrate I/L concurrent deflection and protrusion and limited lateral excursion to C/L side
S curve: NM coordination problem
Cause of deflection to I/L side without return
disk involvement
Occlusal measurement/classes
-Normal overjet: 3-6mm
-Class II: >6mm
Class III: negative with edge to edge occlusion
Cotton Roll Test
Patient bite down on cotton Roll
- If Sx decrease on I/L side, think joint
- if Sx increase on I/L side, think musce
Normal TMJ HEP programs
- c-spine involvement
- 6x6 controlled opening (every 2 hrs)
- Isometrics with fingers: NOT for strength but for stabilization
- tongue blades: for increasing postop hypomobility
Condylar remodeling program: (for ADD)
- use .5 in surgical tubing
- theoretically improves stabilization and disc/condylar congruency
- Used in conjunction with ionto, mobilization with good results
1. deviate C/L then return to center. If pain free add Bite but release bite prior to returning to center
2. Perform #1 but maintain bite to center
3. Perform with protrusion vs. lateral deviation at next phase
4. Isometric contraction can be introduced with tubing in place via stabilization or tubing distraction
Tx: Clicking due to ADDwR
- Open maximally with opening click and close along protruded path
- contact teeth with protrusion, then retrude just prior to closing click (disc repositioning mandibular position)
- Open mouth maximally without opening click
* *Perform 5 min after meals and maintain repositioning position all day; goal is to recapture disc
Tx: PDD:
-use same strategies as ADD, but avoid max mouth opening with submax ROM ex
Tx: Myofascia pain disorder:
- Spray and stretch–inject if this isn’t successful
- Aerobic exercise and stress management important
- multidisciplinary approach most important due to need to address multiple factors
Tx: Trismus
- active opening with head (?)
- Relaxation and diaphragmatic breathing
- US or TENS for spasm
- soft diet 1-2 weeks
- STM and passive stretches
Postop-
- arthrocentesis perferred for severe pain if conservative Tx doesn’t solve issues
- Ice, NMES, US followed by STM and gentle joint mobs
- Graded opening with tongue blades
TX: ear Sx
TMJ and C1-C3 mobilization
TX: Headache
- Acupressure
- 6x6 postural exercises
- relaxation and aerobic exercise
Repositioning splint
recapture anteriorly displaced disc and/or manage disc/ condyle discoordination
-worn 24/7
-worn weeks–>months
Goal: reposition disc
Resting splint
Relaxing and balancing soft tissue
- worn day/night only to decrease stress with clenching/bruxing
- don’t wear with eating
Night Splint
Acrylic resin interocclusal
-helps with muscle relaxation and protects teeth while clenching at night (prevents wear to enamel)
Arthroscopic surgery
good results to decrease pain if conservative treatment fails
-purpose: improve kinematics of disc condyle component through release of soft tissue adhesions and capsular fibrosis
Arthrocentesis surgery
Lavage of joint w/o viewing joint space
TM ligament
AKA lateral ligament: supports lateral wall of JC
- Superficial oblique fibers: limit condylar head rotation during jaw opening
- Deep horizontal fibers: limit posterior displacement of condyle (protects retrodiscal pad)
Collateral LIgaments
Restrict excessive medial and lateral movement of disk so disk centered on top of condyle and moves as unit in AP direction
Masseter muscle functions
U/L: lateral deviation to same side
B: mandibular elevation
Temporalis muscle functions
U/L: lateral deviation to same side
B: elevate and retract mandible
Medial Pterygoid muscle functions:
U/L: C/L deviation
B: elevation and protrusion of mandible
Lateral Pterygoids muscle functions
U/L: C/L deviation
B: protrusion
Centric Relation:
position where condyle sits most superiorly and posteriorly in mandibular fossa with articular disk stabilized in b/t
-AKA open pack; all connective tissues at ease
TMJ movement with cervical flexion vs extension vs. SB/rotation
C-flexion: mandible moves superiorly and anteriorly
C-extension: mandible moves inferiorly and posteriorly
C SB/Rotation: max occlusion occurs on I/L side
Trigeminal nerve (CN V): sensation and reflex
Sensation: midline of forehead and face
DTR: chin reflex
Chvostek sign (Weiss sign)
for facial nerve (CN VII)
-patient sitting, PT taps parotid gland overlying mass of muscle, if facial muscles twitch (nose/lips) + for hypocalcemia with hyperexcitability of nerves
