OCS Chap 3 TMJ Flashcards
mm involved in elevation (closing)
masseter, temporalis, medial pterygoid, superior fibers of lateral pterygoid (stabilize the disc)
mm involved in depression (opening)
inferior fibers of lateral pterygoid, suprahyoids, infrahyoids (indirectly)
mm involved in protrusion
superficial masseter, medial pterygoid, lateral pterygoid
mm involved in retrusion
deep fibers of masseter, temporalis, suprahyoids (digastrics)
lateral excursion
ipsilateral temporalis and masseter, contralateral medial and lateral pterygoids
normal amount of depression
40 to 45 mm for males
45 to 50 mm for females (4 fingers width)
functional is 35 mm or 3 fingers width
depression arthrokinematics
early phase depression - anterior rotation of condylar head in the inferior joint cavity
late phase superior cavity - anterior translation of the disk and the condylar head along the articular eminence
opposite for elevation
protrusion arthrokinematics
mandibular condyle (head) and disk translate anteriorly and inferiorly
opposite for retrusion
lateral excursion arthrokinematics
spinning of the ipsilateral condyle and horizontal anterior translation of the contralateral condyle
anterior disk displacement with reduction (ADDwR)
disk rests in front of the condylar head while the mouth is closed
during opening the disk reduces back,
during closing the disk moves posteriorly until it cant causing a second click (reciprocal clicks)
anterior disk displacement without reduction (ADDwoR)
disk may stay displaced in front of the condyle throughout the movement of mouth opening and closing, due to a progressive decrease in elasticity of the posterior stratum fibers
no clicks
may limit mouth opening (if the disk is blocking full anterior translation) or no limitation (if the disk is completely displaced anteriorly)
posterior disk displacement
rare
occurs after wide opening of the mouth
lateral pterygoid mm is overly stretched
demo open-lock (inability to close mouth)
orthognathia
branch of oral medicine dealing with the cause and treatment of malposition of the bones of the jaw
stomatognathic system
structure of the mouth, teeth, jaw and associated soft tissues
overbite
measure by the portion of the mandibular central incisors that is covered by the maxillary central incisors when the mandible is in its maximally occluded position
overjet
horizontal distance between the maxillary arch and the mandibular arch
normal value is 3 to 6mm
lateral excursion
horizontal distance between the dividing lines of the mandibular central incisors and the maxillary central incisors measured by asking the patient to move the mandible to one side
normal lateral excursion is 25% of the amount of mouth opening
C curve indicates
capsular pattern
S curve indicates
poor motor control or asymmetry of condylar head rotation or translation in an individual w/ ADDwR
deflection
indicated that during opening of the mouth, the mandible deflects to one side w/o returning to the central position at the end of mouth opening (pt w/ ADDwoR)
also occur due to capsular restriction or unilateral hypomobility (deflection towards ipsilateral side)
occulsion
functional relationship between the maxillary teeth and the mandibular teeth
Class 1 occulsion
normal teeth alignment
Class 2 occulsion
excessive overjet of more than 6 mm
Class 3 occulsion
mandibular arch protrudes in front of the maxillary arch (underbit)
open bite
rare oral condition maxillary front teeth do not make contact w/ mandibular front teeth
crossbite
occlusal irregularity where the central incisors of the mandibular and maxillary teeth are not perfectly aligned when the mouth is closed
centric relation
many definitions
open pack position
where the condyle sits most superiorly and posteriorly in the mandibular fossa with the articular disk stabilized between the condyle and fossa
vertical dimension
indicate the superior inferior relationship of the maxilla and mandible when the teeth are situated in maximum intercuspation
freeway space (FWS)
space between the occluding surfaces of the maxillary and mandibular teeth when the mandible is in its physiologic resting position (normal is 2 to 4 mm)
clenching
parafunctional behavior that can occur during the day or while sleeping at night
bruxism
excessive teeth grinding, most frequently while sleeping
TMD can be classified in 3 groups
articular disorders
masticatory mm disorders
arthritides
3 clinical scenarios for deflection
- ADDwoR w/ deflection occurring to side of ADDwoR
- limited capsular mobility deflection occurring towards restriction
- unilateral TMJ hypermobility deflection occuring away from hypermobility
cotton roll test
differentiate between muscular and joint involvement
biting down on an object with back molars will result in gapping (unloading) the ipsilateral TMJ and compressing (loading) contralateral TMJ
when pt complains of pain on one side of the jaw - bite down on cotton roll with the back molars on the side of complaint
pain increases = cause of symptoms may be muscular in origin due to activation of the ipsilateral masticatory mm
pain decreases = cause of original pain may be joint related (disk or retrodiskal pad) because unloading the joint results in a decrease in pain
cranial nerve V reflex
tappin the chin w/ reflex hammer
cluster of tests for ADDwoR
(positive 5 of 7)
joint provocation test (mouth opening with pain
deviation test (deflection to the ipsilateral side at end of mouth opening
laterotrusion test (limited lateral excursion, less than 9 mm ot the contralateral side)
joint mobility test (reduce anterior translation of the condylar head as assessed with palpation extraorally)
joint sound test (absent joint noise or crepitus is considered positive)
dental stick test (tongue depressor place between back molars for patient to bite down on, pain elicited in either the ipsilateral or contralateral joint is considered positive while pain in the surround area is considered neg)
isometric test (manual iso resistance to lateral excursion contralateral, with the test considered positive if pain is elicited)
capsular involvement signs
palpable tenderness over the lateral capsule of the TMJ, pain w/ opening, limited opening w/ deflection to the ipsilateral side, limited lateral excursion to the contralateral side, and deflection towards the ipsilateral side during protrusion
ankylosis of TMJ
restricted joint play mobility and mandibular ROM for mouth opening, protrusion, and contralateral lateral excursion (if unilateral)
hypermobility of TMJ characterized
greater than 55mm
trismus
acute closed lock of the jaw after dental procedure
spasm of masseter mm
myositis
acute inflammation of a mm
dystonia
neurological condition w/ central nervous system (CNS) origin
unable to voluntarily control movement
trigeminal neuralgia (tic douloureux)
paroxysmal, unilateral, electric like, stabbing pain that occurs intermittently and abates within seconds or min
temporal arterities
condition cause by subacute inflammation of the superficial temporal artery and the vertebral artery
clinical presentation includes severe unilateral or bilateral headache over the scalp-temporal artery region - jaw claudication w/ pain or stiffness during chewing is highly suggestive due to ischemia of the mm - ophthalmologic eval is vital due to danger of vision loss
atypical odontalgia (phantom tooth pain)
constant, burning, or pressure like pain, that occurs after endodontic procedures and dental extraction (caused by disruption of neural pathways to the alveolar or pulp)
post herpetic neuralgia (herpes zoster)
constant, severe, burning, or stabbing pain over the distribution of the first division of the CNV
shingles
meniere disease
combination of vertigo, tinnitus, and aural fullness and facial TMJ pain
controlled opening exercises for TMJ dosing
6 reps of each exercise to be performed 6 times a day
such as control mouth opening exercise
condylar remodeling exercise program
neuromuscular re edu of TMJ
patient lightly bites down on rubber tubing w/ incisors then translate rubber tubing to contralateral side (away from pain) then returns to middle position
