Dent 5121
PHYSICAL EVALUATION I
Extra-oral Examination
TMJ & Muscles of Mastication
Richard P Madden DDS MS
RMadden@umn.edu
Lecture Objectives
After today’s lecture, the student will be able to:
Describe the anatomy and function of the
temporomandibular joints and muscles of mastication.
Describe how to examine the function of the
temporomandibular joints and muscles of mastication
and how to record the findings in the dental record.
Describe some common abnormal findings and
disorders associated with the temporomandibular joints
and muscles of mastication.
Temporomandibular joint
Temporomandibular joint
Sphenoid
Temporal bone
Temporomandibular joint
www.doctorspiller.com
Mandible
Muscles of mastication
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Masseter
Temporalis
Medial pterygoid
Lateral pterygoid
http://www.images.md.floyd.lib.umn.edu/users/image_show.asp
Muscles of mastication

Masseter
Temporalis
Medial pterygoid
Lateral pterygoid

Opening, closing, lateral, protrusion, retrusion.



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Gravity assists with opening

The digastric muscle is not considered a muscle of
mastication, but is active in opening
Temporomandibular Joint Anatomy

Temporomandibular joint
TMJ capsule

Ligaments

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
Holds articualr disc
Holds in synovial fluid
that lubricates the joint
Articular disc



Fibrocartilagenous
Mostly devoid of blood
vessels and nerves
Moves with the condyle
Temporomandibular Joint Anatomy

Temporomandibular joint
Compound joint

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Temporal bone
Mandible
Articular disc
Rotates and translates

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Rotation: hinge movement
Translation: mandible
moves forward
Ginglyoarthroidal joint
Disc
Disc
2
Normal TMJ
Posterior attachment
Articular disc
EAM
Condyle
Articular
eminence
Lateral pterygoid
Normal TMJ - translation
Temporomandibular Disorders are
functional disturbances of the masticatory system
“a collective term used for a number of clinical problems that involve
the masticatory muscle, temporomandibular joint (TMJ), and/or
EF Wright -Manual of Temporomandibular disorders
associated structures.”
Muscles of mastication
Temporomandibular joints
Temporomandibular Disorders

Diagnoses involving the muscles of mastication
 Myalgia
 Myofascial
pain
Temporomandibular Disorders

Muscles of Mastication

Myalgia (muscle pain)
 Symptoms


Pain in localized area of one masticatory muscle (usually
masseter or temporalis)
Fatigue with chewing
 Signs


Tender muscles upon palpation
Sometimes limited active vertical range of mandibular
motion
Active Range of Motion: How far the patient opens on their own
Passive range of Motion: How far you can stretch the vertical opening
Temporomandibular Disorders

Muscles of Mastication

Myofascial pain (muscle and fascia pain)
 Symptoms




Regional pain in area of masseter or temporalis muscles
Tinnitus, vertigo, toothache, tension-type headache
Fatigue with chewing
May have limited mandibular function secondary to pain
 Signs



Multiple tender areas in several masticatory muscles upon
palpation
Tender areas may refer pain to other locations in face
Sometimes limited active vertical range of mandibular motion
Temporomandibular Disorders
Masticatory Muscle Pain
Myofascial pain
(muscle and fascia pain)
 Symptoms
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(muscle pain)
 Symptoms

Regional pain – many muscles
Associated symptoms
 Tinnitus, headache,etc
Fatigue with chewing
May have limited mandibular
function secondary to pain
Signs

Myalgia
Multiple tender areas
Possible referral of pain
Possible limited active vertical
range of mandibular motion


Localized pain – one
muscle
Fatigue with chewing
Signs


Tenderness to palpation
Possible limited active
vertical range of
mandibular motion
Temporomandibular Disorders

Diagnoses involving the temporomandibular joints
Disc displacement disorders
 Inflammatory disorders: Capsulitis/arthritis
 Subluxation/dislocation
 Deviation in form

 Congenital / developmental
Ankylosis
 Fracture

Temporomandibular Joint Sounds
Temporomandibular Disorders

Temporomandibular joints

Disc displacement with reduction
 Symptoms
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Clicking or popping noise in TMJ
May feel “catching” in TMJ
 Signs
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Reciprocal click
May have deviation in active vertical mandibular range of motion
and/or in protrusion
No restriction in active vertical mandibular range motion
Reciprocal Click: Click is evident both upon opening and closing
Anterior Disc Displacement


Anterior disc
displacement with
reduction
TMJ sound:


Reciprocal click
or
Reproducible opening
click
Temporomandibular Disorders

Temporomandibular joints

Disc displacement without reduction (Closed lock)
 Symptoms


History of clicking or popping noise in TMJ (past, not now)
Limited mandibular range of motion
 Signs
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No TMJ sounds
Restriction in active vertical mandibular range motion and
laterotrusion
May have deflection in active vertical mandibular range of
motion and/or in protrusion
Anterior Disc Displacement

Anterior disc
displacement without
reduction

TMJ sound:


No click
Possibly crepitus
Temporomandibular Disorders

Temporomandibular joints

Capsulitis/arthritis
 Symptoms



Pain in TMJ or in front of ear
Pain exacerbated by jaw function
May have limited mandibular function secondary to pain
 Signs
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TMJ tender to palpation
TMJ pain worsened upon clenching
Limited active mandibular range of motion, laterotrusion,
protrusion
Temporomandibular Disorders

Temporomandibular joints

Arthritis of TMJ
 Symptoms

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
Pain in TMJ or in front of ear
Pain exacerbated by jaw function
May have limited mandibular function secondary to pain
 Signs
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3

TMJ tender to palpation
TMJ pain worsened upon clenching
Limited active mandibular range of motion, laterotrusion, protrusion
TMJ sound: Fine to coarse crepitus
Radiographic / Imaging: Bony changes: Articular, Glenoid fossa
Bite changes
TMJ Imaging
Normal Computed Tomographic (CT) Image of TMJ
TMJ Imaging

Osteoarthritis / Sclerosis CT Image of TMJ
TMJ Imaging
Cone Beam CT of TMJ
Temporomandibular Disorders

Temporomandibular joints

Subluxation/dislocation (Open lock)
 Condylar head moves too far beyond the articular eminence
 Symptoms


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Jaw “catches” open when yawning or opening mouth wide (if gets
stuck open then dislocation)
Pain in TMJ when jaw gets stuck
Loud pop when opening wide
 Signs
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Excessive active mandibular vertical range of motion
Eminence pop
Residual tenderness in TMJ upon palpation if recent episode
Deviation in Form of TMJ
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Alteration in surface of:
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TMJ sound:
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Articular surface of mandibular condyle
Articular surface of articular eminence of temporal bone
Superior or inferior surface of articular disc
Reproducible opening click
Reproducible closing click
Reproducible opening and closing click
Deviation in form

Congenital / developmental

Deviation in form of the TMJ
Congenital / developmental
 Alteration in surface of:

 Glenoid fossa / eminence
 Articular disc
 Condylar head

TMJ sound:
 Click, crepitus, pop…
Temporomandibular Disorders

Ankylosis


immobility and consolidation of a joint due to disease,
injury, or surgical procedure.
(Dorland’s medical dictionary)
 (bony or fibrous)
Fracture

a break in continuity of bone
(Dorland’s medical dictionary)
 For the TMJ it would usually be the condylar neck
Temporomandibular Disorders
Clinical Examination
Screening Questions
•
•
•
•
•
•
•
•
Pain in jaw/temples/ears?
Fatigue/stiffness in jaw?
Difficulty opening?
Locking open/closed?
TMJ noise?
Trauma to jaw/face?
Change in occlusion?
Oral habits?
Screening Examination

Range of mandibular motion


TMJ

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Noise
Pain
Pain to palpation

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Vertical opening (active)
TMJ
Masticatory muscles
Occlusion

Baseline with shimstock
(Active vs. Passive opening)
Extended Examination

Range of mandibular motion

Vertical opening

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Limitation
Deviation/deflection
Active / passive

Limitation
Symmetry
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Limitation
Deviation/deflection
TMJ
Masticatory muscles
Occlusion


Noise
Pain
Pain to palpation

Protrusion

TMJ

Lateral movements
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Baseline with shimstock
Cervical muscles
Screening Examination

Range of mandibular motion

Vertical opening

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
TMJ

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Noise
Pain
Pain to palpation

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Limitation
Active
TMJ
Masticatory muscles
Occlusion

Baseline with shimstock
Active Range of Motion
Vertical opening
Overlap
Adjust for overlap of incisors
Overjet
Active Range of Motion
Normal Active ROM: 40-60 mm
Males>Females
Pattern of Opening
Deviation on Opening
The opening pathway deviates from
a straight opening, but the midline
relationship returns to normal at
maximum opening.
Deviation on Opening
What could cause such a deviation?
Which TMJ is involved?
Deflection on Opening
The midline deviates to one side upon
opening. The deviation increases with
increased opening and does not return to
normal midline relationship until closure.
Deflection on Opening
What could cause such a deviation?
Which TMJ is involved?
Lateral Range of Motion
Midline off +1 mm left
Normal Lateral ROM >7 mm, Males>Females
Adjusted for deviation in midlines
Looking for symmetry in lateral movements
Lateral Range of Motion
Left lateral movement
9 mm movement to left - 1mm = 8 mm left lateral range of motion
Lateral Range of Motion
Right lateral movement
7 mm movement to right + 1mm = 8 mm right lateral range of motion
Occlusal Contacts
Occlusal Contacts
Tempormandibular Joint

Locate the TMJ by palpating while patient opens and closes mouth
Tempormandibular Joint

Palpate TMJ for
joint noises
Tempormandibular Joint

Auscultate TMJ noises
(not routinely done)
Tempormandibular Joint Sounds
Palpation of TMJ

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After mandibular range
of motion assessment
Locate TMJ
Teeth slightly apart
Not clenching
Not opening and
closing
Muscles of
Mastication
Temporalis Muscle

Origin:


Insertion:


Temporal fossa
Coronoid process,
anterior border of ramus
Function:

Elevates and retracts
mandible, clenches teeth
Temporalis
Muscle
Anterior,
Middle and
Posterior
portions of the
temporalis muscle
should be palpated
Temporalis Muscle
To locate the muscle, have the patient clench.
Apply about two pounds of pressure.
Temporalis Muscle
Anterior
Middle
Posterior
Masseter Muscle

Origin:



Insertion:


Superficial portion – anterior 2/3
of lower border of zygomatic
arch
Deep portion – medial surface of
zygomatic arch
Lateral surface of ramus,
coronoid process, and angle of
mandible
Function:

Elevates mandible, clenches teeth
Masseter Muscle
Palpate multiple areas of
the masseter muscle
Masseter Muscle
Anterior superior portion
Posterior inferior portion
Medial and Lateral Pterygoid Muscles

Difficult to palpate and
questionable reliability.
Temporomandibular Disorders are
functional disturbances of the masticatory system
“a collective term used for a number of clinical problems that involve
the masticatory muscle, temporomandibular joint (TMJ), and/or
EF Wright -Manual of Temporomandibular disorders
associated structures.”
Muscles of mastication
Temporomandibular joints