TMJ Pathology & Diagnosis First Lecture Flashcards
Congenital or Developmental
Disorders
(4)
Aplasia
Hypoplasia
Hyperplasia
Neoplasia
Aplasia
What is it?
— is the most common
developmental defect.
Unilateral or bilateral?
— is often affected
(2) on opening may occur
Rare
More SEVERE than — !
Faulty or incomplete development of the cranial
bones or mandible.
Lack of condylar growth
Either
Auditory apparatus (i.e. Pinna of
ear deformed)
Occlusal shift & deviation
Hypoplasia
Developmental/Congenital
Anomalies affecting TMJ
Aplasia-
Lack of condylar growth is the
most common developmental defect.
Occlusal shift & deviation on opening may
occur. Rare
Treatment of
Condylar Aplasia
(3)
Osteoplasty
Correction of malocclusion
Other surgical treatment possible
depending on function and
esthetics
Hypoplasia
(4)
Incomplete development/underdevelopment of the cranial bones or the
mandible.
Congenital or acquired (i.e. Treacher-Collins syndrome).
Growth is normal but proportionately reduced & less severe than in
aplasia
Condylar hypoplasia can be secondary to trauma.
Treacher-Collins syndrome:
mandibulofacial dysostosis
(4)
- Downward-slanting eyes
- Notched lower eyelids
- Underdeveloped midface
- Deafness
Mandibular Hypoplasia:
High risk for
obstructive sleep
apnea
Mandibular Hypoplasia
Post-treatment with
mandibular advancement
surgery (bilateral sagittal
split osteotomy)
skipped
Condylar Hypoplasia
(2)
Congenital: (2)
Acquired: (6)
Unilateral or bilateral
idiopathic, early onset
forceps deliveries, trauma
especially after jaw fracture, radiation,
infection, circulatory disorder, endocrine
disorders
Condylar Hypoplasia
What is it?
Can be secondary to…
Growth is normal but proportionately reduced & less severe than in
aplasia
Condylar hypoplasia can be secondary to trauma.
Pt. fractured R. condyle at age 6. Panorex- age 15
Condylar
Hypoplasia
Clinical
Symptoms
If unilateral:
(3)
Facial asymmetry
Limitation of lateral
excursion
Mandibular midline
shift
Hyperplasia
What is it?
(2)?
— increase in the number of
normal cells.
Localized:
Mandibular —
Overdevelopment of cranial bones or mandible.
Congenital or acquired.
Non-neoplastic
condylar hyperplasia
prognathism
Mandibular prognathism –
excessive size of
mandible causing protrusion of chin but normal
condyle size, shape, & function
Mandibular Hyperplasia
tx (3)
LeForte I Osteotomy
Bilateral Sagittal osteotomy
Chin Augmentation
Condylar Hyperplasia
Clinical Symptoms
If Unilateral growth, it will cause:
(2)
- A progressive crossbite on the
contralateral side - Open bite in adults
Treatment of Condylar
Hyperplasia
(5)
Leave alone
Wait until after mandibular growth is completed
Orthognathic surgery & possible osteotomy of enlarged
condyle
Orthodontics
Symptomatic care
Coronoid Hyperplasia
(3)
Coronoid Impingement may result from
benign overgrowth of the coronoid
process
May result in limited jaw opening
Visible on Panorex, CBCT, MDCT or MRI
Unilateral Condylar Hyperplasia
creating malocclusion
Transpharyngeal projection:
Condylar head is enlarged,
and the neck is thick.
Neoplasia
What is it?
RARE as an underlying
cause of —.
–% of malignant
neoplasias (breast,
prostate, lung
cancers)metastasize to
the mandible
can affect …
Benign, malignant, or
metastatic from a
distant site.
Uncontrolled growth of
abnormal tissue.
TMD
1
condyle (I.e.
osteoma, fibrous
dysplasia,
chondrosarcoma, benign
giant cell tumor)
OSTEOCHONDROMA
R L
Benign, Solitary Osteochondromas (OCs) arise in response
to an event (e.g. trauma, X-radiation) [1] rather than as
a true neoplasm. Typically, OCs represent –% of all
bone tumors and ~–% of benign bone tumors
10-15
35
OSTEOCHONDROMA
* OCs generally occur in …
* Bones that form from a — are susceptible to single or
multiple osteochondritic lesions.
* This species of bone tumor frequently remains
asymptomatic until they become large enough
to interfere with …
young adults (~30 y/o),
but also appear during middle age or later
(~≥ 50y/o).
cartilage anlagen
(e.g., mandible)
mandibular function (i.e.
opening, lateral excursion) or cause a shift in
the midline & malocclusion.
Neoplasia
Rare in — but more
common in —
Benign:
Malignant:
Consider (2)
condyle, ramus
does not usually
destroy bony margins
Usually destroys
bony margins- Examine cortical
outline of mandible on Panorex
parotid and regional
carcinomas
Hypermobility Disorders: 2 types
of TMJ Dislocations:
Hypermobility disorders include two types of TMJ dislocations
in which the
disc-condyle complex is positioned anterior to the
articular eminence and is unable to return to a closed position
without a specific maneuver by the patient (i.e., subluxation or
partial dislocation) or by the clinician
Subluxation
(3)
Partial or incomplete condylar
dislocation during wide mouth opening
but the patient can close voluntarily
Usually accompanied by a joint sound
(soft pop or click)
May result from anatomical
difference , habit, or trauma
Diagnosis of Subluxation
(4)
Normal translation beyond eminence which
does not lead to open lock (luxation) & condyle
can return to mandibular fossa voluntarily.
Soft pop at maximum opening
Deviation to opposite side (if unilateral)
Excessive translation on opening
Treatment of Subluxation
(5)
- Retruded opening exercises
- Control yawn with hand under chin; Avoid Big
Macs, cut up apples and fruits into small pieces - AVOID prolonged mouth opening at DENTAL APPT.-
this can cause an open lock. - Manage muscle hyperactivity
- Eminectomy (surgical reduction of articular
eminence)
Dislocation of Condyle
(Luxation, open lock)
(4)
Condyle is forcibly moved beyond the articular
eminence
Unable to return to a closed position voluntarily
May be caused by yawning, dental appt. or
trauma
Sudden open lock of jaw
Diagnosis of Dislocation of Condyle
(Luxation, open lock)
1. What is it
2. Radiograph reveals
3. The dislocation may be
4. — may accompany dislocation and persist
afterwards.
Inability to close the mouth without a specific
manipulative maneuver
that condyle translates
well beyond the eminence
momentary or prolonged
Pain
Treatment of Dislocation of Condyle
(Luxation, open lock)
(4)
- Seat the patient upright.
- Ask pt to relax the jaw muscles.
- Apply digital pressure to move mandible in inferior &
posterior direction. Requires significant force. Call
ORAL SURGEON in clinic if available. - Rx: NSAIDs or Muscle Relaxants for pain
Types of Ankylosis
(4)
- Bony
- Fibrous
- Intra-articular
- Extra-articular
Ankylosis
(2)
Temporomandibular joint ankylosis represents
fibrous or bony fusion between the mandibular
condyle and fossa, which is
usually traumatically caused by condyle fracture.
(1)
It could also be caused by infections, degenerative
diseases, injection of corticosteroids, forceps
delivery and complications of TMJ surgery
Right TMJ
Ankylosis
— is best for detecting boney
ankylosis
— is ordered to detect fibrous ankylosis
Restricted mandibular movement with
deflection to the affected side on opening
CBCT or MDCT
MRI
ANKYLOSIS
Usually develops before age of –,
however, it could develop at any
age.
Patients usually present with
(3)
May be associated with —
10
progressive limitation of mouth
opening, facial deformity, and
obstructive sleep apnea syndrome.
TRAUMA
Bony Ankylosis of R. Condyle with
obliteration of disc space & no condylar
translation :
R L
Condyle is
Fused to
glenoid
fossa
AnkylosisClinical
Exam
Firm, unyielding restriction due to either
Not associated with —
Cannot clinically differentiate between
this condition and other disorders
causing restriction of mouth opening.
May need — to r/o anterior disc
displacement or myospasm, or
exploratory —
intra-articular fibrous or bony ankylosis
pain
MRI, arthroscopy
Diagnosis
of
Ankylosis
Limitation of —
Marked deviation to — side
Marked limited lateral movement to —
side (if unilateral)
—end feel when stretching patient to
maximum opening
Pain?
— may aid in diagnosis but not
always. — may show soft tissue ankylosis.
opening
affected
opposite
Hard
No pain
CBCT or Panorex, MRI
Fibrous
Ankylosis
Imaging reveals …
— is needed for diagnosis
absence of
ipsilateral condylar
translation on opening but
disc space is seen
MRI
Ankylosis
Intracapsular:
Extracapsular:
immobilization located
within the joint
rigidity
of periarticular tissues
(surrounding the joint)
resulting in joint
stiffness or
immobilization
Etiology of Ankylosis
(8)
Abnormal intrauterine development
Birth injury or fractures
Chin trauma (posterior)
Malar-zygomatic fractures
Congenital syphilis
Inflammation or septicemia
Metastatic malignancies
Radiation treatment
Treatment of Ankylosis
(4)
- Range of Motion (ROM)
exercises - Therabite
- Physical therapy
- Surgery
Surgical micro scissors placed
through cannula to cut
fibrous band in lateral
capsular adhesion
