INDIAN DENTAL ACADEMY
Leader in continuing dental education
• Inability to open the mouth beyond 5mm of
inter-incisal opening due to fusion of head of
the condyle of the mandible with the articulating
surface of the glenoid fossa is termed as “
Ankylosis of the TMJ”.
• Inability to open the mouth on account of
muscular spasm or trismus is called as
‘ false ankylosis ’ as the cause here is extra
Ankylosis, or Anchylosis
( from Greek αγκυλος, bent, crooked )
Ankylosis is a stiffness of a joint, as a result of injury
or disease and results in hypomobiliy or no mobility.
1.When the structures outside the joint are involved,
it is termed "false ankylosis”.
1.in contrast when the disease involves the TMJ
itself, it is called "true ankylosis”.
1.When inflammation causes the joint-ends of the
bones to be fused together the ankylosis is termed
“ osseous” or complete.
CLASSIFICATION OF ANKYLOSIS:
1. False ankylosis or true ankylosis.
2. Extra - articular or intra - articular.
3. Fibrous or bony.
4. Unilateral or bilateral.
5. Partial or complete.
ETIOPATHOLOGY OF THE ANKYLOSIS OF
False ankylosis results from pathological
condition outside the joint and leads to limited
CAUSES OF FALSE ANKYLOSIS
1. MUSCULAR TRISMUS
• It can be established because of pericoronitis,
infection adjoining the muscles of mastication
involving submasseteric pterygomandibular,
infra - temporal or submandibular spaces.
2. MUSCULAR FIBROSIS
• Muscular fibrosis from any dysfunction of
long standing like a arthritis and myositis etc.
hampers the jaw movements.
3. MYOSITIS OSSIFICANS
• When there is progressive ossification after
injury and hematoma formation especially of
the masseter muscle, inability to open the
mouth develops. This can be confirmed
radiologically as well.
• When there is hypocalcaemia, the spasms in
the muscles are produced hampering the
opening of the mouth.
• Acute infectious disease caused by
Clostridium tetani is represented by an early
symptom of lock-jaw because of persistent
tonic spasm of the muscles.
6. NEUROGENIC CAUSES
• Neurogenic causes like epilepsy, brain tumour,
bulbar paralysis and embolic hemorrhage in
medulla oblongata are also represented by
hypomobility of the jaw.
7. TRISMUS HYSTERICUS
• It is disease of psychogenic origin. A typical
example is frightening of the lady of the house
causing spasm of the masticatory muscles when a
thief breaks into the house through the window.
8. DRUG INDUCED SPASMS
• Drug induced spasms like in strychnine poisoning.
9. MECHANICAL BLOCKADE
• Mechanical blockade on account of osteoma or
elongation of the coronoid process of the mandible
there by reducing it's movement under the
10. FRACTURE OF THE ZYGOMATIC ARCH
• Fracture of the zygomatic arch with inward buckling
will cause mechanical obstruction to coronoid
process and hence restricting the movements of
11: FRACTURE OF THE MANDIBLE
• Trauma causing fracture of the mandible leads to
reflex spasm of the muscles and hence trismus.
12. SCARS AND BURNS OF THE FACE
• Scars and burns of the face also, restrict the
movements of the jaw. Post irradiation fibrosis lead to
hypomobility of the mandible.
13. CLEFT PALATE OPERATIONS
• can produce fibrosis of the pterygomandibular raphe
and, consequently, limitation of mouth opening.
Moderate degrees of fibrosis can be released or a
coronoidectomy performed if the temporalis muscle is
14. SUBMUCOUS FIBROSIS
• Submucous fibrosis results in tense fibrous bands in
the cheeks and pillars of the fauces which stretch from
mandible to maxilla limiting movement of the mandible,
tongue and soft palate..
• True ankylosis, is a condition that produces
- fibrous adhesions or
- bony union
between the articulating surfaces of TM joint
and may be classified as:
- Fibro - osseous and
- Bony ankylosis.
• Further, it may be unilateral or bilateral and
partial or complete.
1. Birth Trauma
• Birth trauma producing so-called congenital
ankylosis and occurs in cases of difficult
delivery, particularly forceps delivery.
• At times, other bones are fractured as well.
• The injury of the jaw caused by the use of
forceps may not be discovered until later
when it is noticed that the child could open
his jaw only slightly.
• Haemarthrosis is another cause of ankylosis.
It is generally, due to:
- fracture of the base of skull extending
through the mandibular fossa
- may also be caused by an intracapsular
• Cortical bone in a child is very thin - as a result of
intracapsular # of TMJ, bleeding takes place within
the joint – known as hemarthrosis
there is fragmentation of the condyle
this has highly osteogenic potential
the hematoma within the joint organises
which is then converted to fibrous tissue and
then bone resulting in bony ankylosis
3. Suppurative arthritis
• Suppurative arthritis, may be due to infection of
the ear or mastoiditis or it may be of
hematogenous origin leading to ankylosis
4. Rheumatoid arthritis
• Rheumatoid arthritis, may cause great
limitation of motion or complete ankylosis
• There is associated atrophy of the muscles
generally accompaning ankylosis, if
contracted early in life.
Osteomyelitis affecting the mandibular
condyle without involving the joint itself
frequently results in limitation of motion
peri-articular swelling, and suppuration often
results in fistula formation.
6. Fracture of the condyle
Fracture of the condyle, especially comminuted
fractures of the head of the condyle, may cause
The cause may be intra-articular or periarticular
hemorrhage or comminution of the condyle.
Trauma to the condyle in children is more likely to
cause ankylosis than adults.
• This is because condylar structure of
children is different than adults.
In a child the neck of the condyle is short &
stubby but in adults its longer & narrower.
• Due to this trauma - in an adult is likely to #
the condylar neck but in a child it is likely to
cause intra-capsular #
• CLINICAL FEATURES:
Clinical manifestations vary according to:
(a) Severity of ankylosis,
(b) Time of onset of ankylosis,
• 1. Early joint involvement - less than 15 years:
Severe facial deformity and loss of function.
• 2. Later joint involvement after the age of 15 years:
Facial deformity marginal or nil. But, functional loss
• Those patients in whom the ankylosis develops
after full growth completion have no facial
The CLINICAL MANIFESTATIONS of ankylosis vary.
• Pain is not an outstanding symptom, it is present only in
the early stages of the disease.
On inspection see:
• Healed chin laceration in case of trauma as injury to the
chin is usually associated with # of the condyle or
• Reduced interincisal mouth opening or NO mouth
opening at all + neglected oral hygiene + impacted /
malposed /carious teeth.
• Inability to open the jaw and difficulty or inability to
• In cases in which the disease
was contracted early in life, a
so-called ‘bird face’ results.
• This includes
- a receding chin,
- impaction of teeth.
The maxilla may be narrow and
protrude because of the use of
dilators and exercisers to
counteract the freezing of the
• There is underdevelopment of the mandible and is
associated with a prominent angle of the jaw and
curve of the inferior border called ‘ante - gonial
• This ante-gonial notching or curve denotes an
attempt at bending the bone by the powerful
depressor muscles attached to the symphysis, which
come into function when great force is needed to
open the jaw
In BILATERAL ANKYLOSIS you will observe
1. Bird face deformity + micro
2. Inability to open mouth +
inability to masticate
3. Class II malocclusion
4. Deep ante - gonial notching
5. Poor oral hygiene
6. Severe malocclusion with
crowding + protrusive upper
anterior teeth + anterior open
So in UNILATERAL ANKYLOSIS you will find :
1. Facial asymmetry with affected side
appearing normal & the opposite side
2. Chin is deviated to the ankylosed side.
3. This is because the normal side
continues to grow & pushes the
mandible to the affected side giving
appearance of fullness on the ankylosed
4. Ante-gonial notch on the affected side
5. Minimal condylar movements on
6. Class II malocclusion on affected side
and cross bite may be seen
PROBLEMS ASSOCIATED WITH ANKYLOSIS
1. Interferes with the mastication of food and with
2. Prevents oral hygiene and prophylactic care, and
treatment of dental caries,
3. As a result, patients with this ailment generally
suffer from extensive multiple caries and periapical
If the disease is contracted early in life,
4. There is destruction of the growth center
[situated in the condyle] and with absence of
functional stimulation prevents normal
development of the jaw
5. This, in turn prevents normal eruption of the
teeth and causes micrognathia - a disfigurement
which handicaps the patient in many ways.
Diagnosis is based on:
1. History of infection or trauma
(birth trauma + falls + previous infection of the ear)
2. Findings at clinical examination
(reduced interincisal opening + diminished/no
TMJ movements + scar on the chin due to trauma)
3. Radiological findings
For proper evaluation several radiographic views
• Orthopantomograph: OPG will show both the
joints for comparision – important in unilateral
cases –will also reveal ante-gonial notching.
• PA view will show the mediolateral extent of
the bony mass – also reveal any mandibular
• Lateral oblique – will demonstrate the anteroposterior extent of the bony mass and the
elongation of the coronoid process
• CT Scan/3D CT Scan – gives relationship to the
middle cranial fossa and internal carotid artery
(carotid canal) medially to the ankylotic mass –
usually not seen in conventional radiographs.
3D CT SCAN showing Bony Ankylosis
Coronal CT Scan showing
TM Joint Ankylosis
CONE BEAM 3D CT SCAN –The cone beam CT
provides multiple images with unprecedented imaging
of the maxillofacial area with less radiation than
traditional CT beam
• Radiographic changes are of extreme
value in diagnosis
In fibrous ankylosis
1.there is evidence of destructive +
proliferative changes seen in bony
compartments of TMJ +
2.haziness or narrowing of joint space
In bony ankylosis
1.overall obliteration of joint space.
2.It will also show antegonial notching
anterior to the angle of mandible and
3.elongation of coronoid process.
What happens if Ankylosis is left
1. Normal growth & development of face is affected
2. There is Nutritional impairment
3. Speech impairment
4. Sleep apnoea ( tongue falls back in sleep) in Bilateral
6. Poor and neglected oral hygiene
7. Multiple carious and impacted teeth.
KABAN’S PROTOCOL FOR MANAGEMENT OF
1. Early surgical management
2. Aggressive total excision of the ankylotic mass
3. Coronoidectomy + myotomy on the affected side to
eliminate temporalis muscle restriction.
4. Lining with temporalis muscle/fascia
5. If steps 1 + 2 + 3 do not create enough opening,
opposite side coronoidectomy is done.
6. Reconstruction of ramal height with costochondral graft
7. Early post-operative mobilisation and aggressive
physiotherapy for at least 6 -12 months
8. Regular long term follow-up
9. Esthetic /orthognathic surgery to be carried out as a
secondary procedure, when growth has completed
MANAGEMENT OF ANKYLOSIS
Management of Ankylosis
• Treatment of Ankylosis is Surgical & should be
corrected at the earliest.
• WHY ? TO ENSURE EFFECTIVE FUNCTION
• Surgical treatment options will depend on:
1. Age of on set of ankylosis
2. Whether unilateral or bilateral ankylosis
3. Extent of ankylosis and
4. Any associated facial deformity ?
• Aims and Objectives of Surgery
1. Release of ankylosed mass and creation of a gap to
mobilize the joint.
2. Creation of a functional joint.
- To improve patient's nutrition.
- To improve patient's oral hygiene.
- To carry out necessary dental treatment.
3. To reconstruct the joint and restore the vertical height
of the ramus.
4. To prevent recurrence.
5. To restore normal facial growth pattern (based on
functional matrix theory).
6. To improve esthetics and rehabilitate the patient
(cosmetic surgery may be carried out at a later date or
at second phase).
Surgical Approaches to the TMJ
1. Preauricular incision with modifications
2. Submandibular incision
3. Post auricular
4. Post ramal
5. Endaural incision
6. Coronal incision
ALKAYAT - BRAMLEY INCISION
• Alkayat - Bramley incision
is a modification of the
preauricular incision where
the upper part of the
incision is extended in a
question mark fashion over
the temporal area to gain
Pre – surgical operative considerations
In addition to the operative procedure the
following factors must be considered.
1. Intubating the patient for General anaesthesia may be
a problem as the patient has minimal to no mouth
1. Techniques such as blind nasal, fibre-optic or retrograde
intubation may need to be employed.
1. Only when it is not possible to intubate with these
procedures should a tracheostomy be considered.
1. Blood loss may be significant at the time of surgery
especially in children & there should be plans for blood
TIMING OF SURGERY
Surgery for Ankylosis can be done in 2 stages:
• In the first stage surgery, only release of ankylosis
with costochondral graft in young patients is done
to bring about jaw mobility and growth.
• In the second stage surgery an orthognathic
surgery can be planned to restore facial esthetics.
• Some surgeons prefer to use a single stage
procedure where release of ankylosis and esthetic
correction are done in a single stage in adults or
after cessation of growth spurts in children.
Basically these are the VARIOUS types of Surgical
2. Gap arthroplasty
3. Interpositional Arthroplasty.
4. Ramus Osteotomy
5. Angle’s Osteotomy
Use of Brisement Force
• The forced opening of the jaw with the patient under
general anesthesia is the oldest method that has
• The jaw is forced open by means of a mouth gag and
mobilized as much as possible by forceful
• In FIBROUS ANKYLOSIS or immobility caused by muscle
spasms or fibrosis, this method may yield good
• After the jaw has been mobilized, the patient is further
benefited, by exercises by various exercisers or with a
rubber block / acrylic screw / jaw exerciser inserted
between the teethwww.indiandentalacademy.com side.
on the affected
Condylectomy and Arthroplasty
• Surgical procedures for mobilisation of an
ankylosed joint were first described by
* Esmarch in 1851
* Murphy 1913
* Blair 1928
They reported that Arthrolysis is unsatisfactory, and
it is usually followed by recurrence, but that
condylectomy and osteoarthrotomy are satisfactory
• In both condylectomy and osteoarthrotomy the
condyle is removed.
• The two methods do not differ a great deal,
except for the amount of bone excised.
• In a condylectomy the condyle is detached and
• an osteoarthrotomy includes the excision of the
entire joint and / or an adequate amount of bone
below the joint
• Condylectomy consists of excision of the condyle.
It is indicated in:
2.various types of arthritis,
3.in malunited condylar fractures with limitation of
motion and pain during mastication.
4.Condylectomy can also be performed in cases of
fibrous ankylosis where the articular space has not
been completely eliminated.
Complications / Disadvantages of Condylectomy
1.Loss of vertical height of the ramus.
1.In case of bilateral condylectomy, it may create
an anterior open bite.
1.In unilateral cases, there may be deviation of
the jaw on opening.
• In bony ankylosis
- the condyle is completely fused to the base
of the skull
- the sigmoid notch is lost by broad
enlargement of the condylar head and
- the coronoid is small size, often elongated
• Because the joint is completed eliminated by the
disease, or bony mass - an osteoarthrotomy or a
double osteotomy is performed to remove a slice of
bone, which is known as ‘ gap arthroplasty ’.
• In gap arthroplasty, a piece of bone about 1.5 to 2 cm
in width is removed.
• Since there is a tendency for ankylosis to recur, some
autogenous / alloplastic material should be interposed
• Care should be taken while removing bone from the
medial aspect of the TM Joint so as not to injure
structures in close proximity, such as the maxillary
artery and the carotid canal.
• The mouth is forced open with the help of a mouth gag
to check the mouth opening -a gap of 1.5 - 2 cms is
created & not interposed with any material.
• Post-op, this gap is maintained by active
physiotherapy to prevent re-ankylosis.
• When adequate movement and mouth opening cannot
be achieved, it may be necessary to osteotomise the
coronoid process also.
Left Preauricular Incision showing surgical exposure and
the Ankylotic bony mass TMJ - left side
Right Surgical exposure showing the condyle fused to the
zygomatic arch forming a ankylotic mass
Left Ostoetomy Cut
Right After the osteotomy, a gap of at least 1.5 – 2 cms
between the roof of the fossa and the mandible is made.
III. Interpositional Arthroplasty
• Interpositional arthoplasty is similar to the gap
arthroplasty and can be performed via a preauricular + submandibular incision or both can be
used, when costochondral grafting is done.
• Placing a interpositional material between the two
bony cut ends avoids contact between them and
thus minimises chances of re-ankylosis.
• Various interpositional materials have been used
which can be either alloplastic materials or
• ALLOPLASTIC MATERIALS such as silastic,
acrylic etc., have been used. Another excellent
material is Teflon such as is used for vascular
• AUTOGENOUS MATERIALS such as temporalis
muscle, temporalis fascia, skin grafts, auricular
cartilage, fascia lata etc; have been attempted.
Left After the osteotomy, a gap of at least 1.5 – 2 cms between the roof
of the fossa and the mandible is made. Interpositional material –either
Autogenous or alloplastic can be inserted and secured
Right Lining of the Glenoid fossa Finger flap of the temporalis muscle
rotated anteriorly under the zygomatic arch into the glenoid fossa
Ipsilateral coronoidectomy and temporalis
• In most of these cases there is always an elongated
• After carrying out gap arthroplasty, coronoidectomy on
the same side should be carried out either separately or
in combination with the gap arthroplasty from the same
• The coronoid process is cut at the level of sigmoid notch
till the anterior border of the ramus + the temporalis
muscle attachments are severed by carrying out
• The oral opening is checked after arthoplasty, and if
maximum interincisal opening greater than 35 mm is
obtained, then there is no need to carry out
• But, if maximum inter-incisal opening is less than 35
mm Then coronoidectomy + temporalis myotomy
on the uninvolved side, can be carried out through an
• Lining of the glenoid fossa is done with temporalis
muscle / fascia.
IV. RAMUS OSTEOTOMY:
• An operation in which osteotomy of
ramus is done and a pully like
structure is inserted between the
V. ANGLES OSTEOTOMY:
• Angle osteotomy in which
masseter and medial pterygoid
muscle are interposed between the
fragment to prevent relapse.
USE OF COSTOCHONDRAL GRAFT
• In children, after the release of the ankylosis. it is
necessary to place a material that will allow growth
• A costochondral graft is harvested from the 5th 6th or
• A costo-chondral junction of about 1.5 cm is
harvested and attached to the lateral surface of the
ramus of the mandible to reconstruct the ramus.
• Thereby a functional and anatomical joint is created.
• Cosmetic surgery is carried out at the later date
when the growth of the patient is completed.
Costochondral Graft can be fixed with either
miniplates or lag screws
Complications of costochondral grafting
1.Second surgical site
2.Donor site complications such as pleuritic pain,
3.Excessive growth of the graft beyond what is
required. This can be minimised by taking not
more than 1.5 cm of costochondral graft.
1. After surgery, a pressure dressing is applied
The pressure is accomplished by means of a thick gauze
pack which is held in place by a bandage.
1. The patient is kept on steroids + antibiotic therapy for
7 to 10 days.
1. After 24 hours the dressing is changed and the
rubber drain removed. After 24 to 36 hours the
bandage is omitted and the dressing held by Elastoplast.
1. Immobilization of the jaw by means of intermaxillary
elastics is recommended for the first 7- 10 days and then
the patient is givenwww.indiandentalacademy.com
1. After arthroplasty, especially gap arthroplasty, patient
requires a splint inserted at the time of operation to
prevent scar contracture
1. Scar formation has the tendency to pull the ramus
up, which causes malocclusion and cross-bite
1. The use of a splint to raise the bite increases the gap
between the bone edges so that after the healing is
complete there is a slack which allows the patient to bring
the teeth into occlusion when the splint is removed and
permits free opening of the jaw.
1. In unilateral cases it is also important to guide the jaw
into normal position by means of a guide plane
• Physiotherapy is as important as the surgery itself.
• The patient should be encouraged to start active
exercises of the jaws as soon as it can be tolerated.
• Pressure with finger or simple finger exercises to gently
force the mouth open initially; ice cream sticks / tongue
blades / acrylic screw / jaw exerciser.
• A mouth gag can be used for forceful mouth opening at a
• During physiotherapy, medications can be given to relieve
pain and enable movement.
• Heat application to the joint region prior to exercise
permits easy movement by relieving muscle spasm.
COMPLICATIONS DURING TM JOINT
• DURING ANAESTHESIA
1.As the patient cannot open the mouth, awake
blind intubation has to be done, especially where
patients cooperation is required, which is very
difficult to obtain from younger patients.
2.Because of small mandible and altered position of
the larynx, intubation poses a problem
3.Aspiration of blood clot, tooth or foreign body
during extubation as throat cannot be packed prior
4.Danger of falling back of tongue and obstructing
airway is always after extubation.
• DURING SURGERY
• Hemorrhage due to damage to any of the superficial
temporal vessels, transverse facial artery, inferior
alveolar vessel and internal maxillary vessels,
pterygoid plexus of veins.
• Damage to external auditory meatus.
• Damage to zygomatic and temporal branch of facial
• Damage to glenoid fossa and thus perforation into
middle cranial fossa.
• Damage to auriculotemporal nerve.
• Damage to parotid gland.
• Damage to the teeth during opening of the jaws with
jaw stretcher / mouth gag.
• DURING POSTOPERATIVE FOLLOW-UP
3.Recurrence of ankylosis.
• What are the most important deterrent to
Three factors, namely:
1.Creation of a gap of sufficient width ( 1.5 -2 cm)
2.Careful application & stabilization of suitable
interpositional medium that completely covers the
surfaces of sectioned bone
3.Jaw exercises done sincerely over a period of
Of the above 3 factors, the use of exercises is
probably most important.
That’s it ……..Thank You