Hypertranslation, Subluxation, and Dislocation
Normally the condyle, translates to the inferior aspect of the articular eminence on full opening. Hypermobility means “Excessive mobility” when applied to the TMJ it refers to a condition of “Hypertranslation”. Hypermobility can be divided into three interrelated clinical entities.
- Hypertranslation refers to the excessive anterior movement of the condyle during opening.
- The term subluxation is defined as a self reducing partial dislocation of the tmj during which the condyle passes anterior to the articular eminence.
- The term dislocation can be defined as long lasting inability to close the mouth due to the complete translation of the condyle anterior to the articular eminence.
- The mandible may depressed (opening of mouth) or elevated (closure of mouth). Protruded / Retracted.
- A considerable amount of restorations occurs. Three activates involve gliding, spin and angulation.
In the position of rest the teeth of the mandible and maxilla are not in contact but slightly separated on closure of the jaws. The teeth come into opposition in the occlusal position.
- Depression of jaw (opening of mouth):
Is accomplished by, lateral pterygoid resistance in the rotation of the head of mandible/condyle digastric, geniohyoid, mylohyoid round a horizontal axis under the articular disc (lower compartment) and the disc (upper compartment) and finally some rotation and gliding of the head (lower compartment) so that the head articulates with most anterior part of the articular disc.
- Elevation of jaw (Closure of mouth):
Is by reverse movements, temporalis, masseter, helical pterygoid of both sides gliding backward followed by rotations of the head (lower compartment) and finally gliding of the disc (upper compartment) due to relaxation of the lateral pterygoid muscle.
- Protrusion (Protraction): is a movement where lower teeth protrude forwards beyond upper teeth (upper compartment) (lateral and medial pterygoid, muscle).
- Retrction: mol is drawn backwards to the position of rest (upper compartment) temporalis muscle posterior fissure.
- An incomplete dislocation of the condyle with maximum opening the condyle translates anterior to the articular eminence and is able to return to the fossa after either self manipulation or spontaneous voluntary retention.
- Subluxation may coexist with internal derangement.
- It usually report a momentarily / short duration of open dislocation with the jaw ‘sticking’ / temporarily inability to close the jaw completely.
- Is on incomplete joint dislocation / partial evaporation of articular surfaces.
- Subluxation is noted by the mandible sticking / catching open for a short period before it reduces itself into the fossae.
- When internal derangement is associated with hypermobility multiple clicks can be detected which represents the condyle snapping over the posterior and anterior edges of the disk.
- “Click” occurs only on wide opening and not on protrusive or lateral movement / excursions.
- Limit mouth opening.
- Exercise not strengthen the elevator muscle.
- Inj of sclerosing solution to reduce the laxity of the capsule.
Etiology of subluxation / dislocation of TMJ:
- Intrinsic trauma.
Over intention injury.
Wide biting, seizure disorder.
- Extrinsic trauma:
Flexion, extension injury to the mandible.
Intubation with general anesthesic.
- Connective tissue disorders:
Shler’c Dantos syndrome.
- Miscellaneous causes:
Dis synchesmous muscle function.
Contralateral intraarticular obstruction.
Host vertical dimensions.
Tradive orofacial dyskensica.
- Drug induced
Predisposing factors to hypermobility (subluxation dislocations)
- Previous capsule and ligament injury.
- Laxity of ligaments (TMJ)
- Degenerative joint disease.
- Systynechenous muscle function.
- Morphologic conditions of the condyle and eminence.
- Subluxation/ dislocation are most frequently caused by the combination of TMJ overextensions and dyssynchromes muscle function.
- Joint over extension may be caused by yawning wide jaw opening / vomiting.
- Dysynchromes muscle contraction results from an alteration of the normal contraction sequelae of the protractor and elevator muscles of the mandible.
- The condyle protractors fail to release of the condyle reaches its most anteroinferior position in relation to the articular eminence on opening and the elevators. Simultaneously contracts to dislocate the mandible into the extratemporal fossae.
- Dislocation may also be a con———- of internal derangement.
- He disk lower to rest between the eminence and posterosuperior surface of the condyle and blocks the return of the condyle to the glenoid fossa.
“Occurs when the condyle moves into a position anterior to the articular eminence (open lock) from which it cannot be voluntarily reduced or repositioned into the glenoid fossa”.
- Dislocation is also called luxation of the TMJ.
- Dislocation of mandible is one of the earliest afflictions of the jaws to be described in the literature.
- Hippocrates is the 5th century described the dislocation and its treatment.
- Mandible dislocation is uncommon compared to other joint dislocations.
- Its incidence is 3%.
- It is uncommon in the extremes of age and there is a higher incidence in females.
- Dislocation most commonly occur in an anterior direction in relationship to the articular eminence.
- Superior, posterior and direct medial dislocations rquires lateral dislocations are associated with fracture of the mandible and are rare.
- Anterior dislocation / subluxations of the condyle may be either unilateral / bilateral.
- They can be 1) Acute, 2) Chronic.
- Acute dislocation:
- Acute dislocation is common.
- Can be brought about by a blow on the chin while mouth is open.
- Injudicious use of mouth gag during G.A. excessive pressure during dental extractions excessive yawning vomiting laughing loudly opening mouth to wide for sating.
- Chronic dislocations types:
- Long standing.
- Recurrent dislocation:
Dislocation which takes place repeatedly and which lost for short/long internals.
- Long standing dislocation:
A dislocation that remains locked anteriorly for several days to years is in old.
- Habitual dislocation:
This term chronic dislocation is appropriately used in those cases where the patient is able to dislocate and reduce at will this condition is often referred or habitual.
- Habitual dislocation is usually associated with psychological factor.
- Chronic dislocation may be an expression of a centrally mediated motor disturbance.
Patient present with hypertranslation without external derangement or dislocation may have c/o capsule and joint soreness.
- temporofrontal headache.
- A sensation of fullness in the TMJ.
- Dislocation C/F:
- In acute dislocation one should carefully assertain the causative event, onset and duration of the dislocation.
- Acute dislocation is easy to recognize clinically.
- The patient presents with acute pain in the affected joint end associated muscles of mastication.
- Dislocation can be unilateral / bilateral.
- Unilateral dislocation:
Difficulty in mastication and swallowing, speaking profuse d rooling of saliva in the early stage.
A deviation of chin toward contralateral side (unaffected side) lateral crossbite, a open bite on unaffected side.
Mouth is partly open and deviation of the midline towards unaffected side.
Palpation of the preauricular area reveals a hollow space anterior to the tregus with the condyle palpable anterior to the articular eminence.
The coronoid process is palpable posterior and inferior to the molar bone.
The capsule structures are tender, quite painful to palpation.
Bilateral acute dislocation:
- Associated with pain.
- Inability to close the mouth.
- Tense masticatory muscles.
- Difficulty in speech, excessive salivation protruding chin.
- The mandible is postured forward and movements are restricted gagging of the molar teeth / posterior teeth with the presence of anterior open bite.
- Difficulty in swallowing and drooling of saliva.
- Patient will C/O pain in the temporal region
- Palpation of the preauricular area reveales a hollow space anterior to the tragus with the condyle palpable anterior to the articular eminence.
- The coronoid process is palpable posterior and inferior to the molar bone.
- The patient is unable to close the mouth/ move the mandible from side to side.
- Absence of the condyle from the glenoid fossae it is often displaced to a position anterosuperior to the anterior articular eminence on both open and closed mouth views.
- Radiographic evaluation is indicated for preoperative evaluation of the morphologic characteristics architecture of the eminence.
- Surgeon importance is pneumatization of the articular eminence.
- In chronic recurrent dislocation radiographic are useful to assess the longterm remodeling changes that have occurred in the condyle and articular eminence before determining the feasibility of surgical reduction.
- the initial acute, long standing and the chronic recurring dislocations of the mandible require different treatments. The acute dislocation needs immediate treatment attention for relief of pain and anxiety to minimize damage to the joint structure.
- Reduction and immobilization for 4 weeks will slow damaged ligaments, capsule, disk to heal.
- The chronic care and the treatment consists of exercise to gain better muscular control and restraint of opening.
Management by surgery may be indicated for long standing and chronic dislocations but rarely for an initial acute dislocations.
- The major problem to overcome in all dislocations is muscle contraction.
There are various approaches to treatment of acute/chronic dislocations of TMJ.
- Non surgical treatment.
- Surgical treatment.
- Non-surgical treatment:
- Digital manipulation:
- a) Manipulation after infiltration of local anesthesia into glenoid fossa. First advocated by Johnson 1958. After dislocation the muscles of mastication are in a state of spasm relaxation of these muscle being required before reduction.
Local anesthetic effect:
- To overcome muscle spasm produced by soft tissue damage associated with dislocation.
- To abolish the muscle spasm produced by raflener during the actual reduction of the dislocation. LA to block the sensory site of local reflexes.
Ex: Pain/ muscle stretch reflexes.
- b) Manipulation muscles G.A. with the muscle relaxants.
- c) Manipulation under either oral / IV sedation (with/without LA).
- d) Slow traction under GA using arch bars digital manipulation firls.
Stimulation of the gag reflex by touching a mouth mirror to the soft palate may inhibit elevator muscle activity. Thus increasing the articular disc space.
2) Physical therapy (Recurrent dislocation):
- The use of isometric exercises to improve opening and closing pattern.
- Patient with chronic subluxation and dislocation have a habit of initial translation during the opening phase.
- Synchronized isometric contraction exercise of masticatory opening muscles and their antagonists should be performed on a regular basis. This results in improvement by strengthening the muscles and there by improving joint stability.
- Exercise trains the suprahyoid muscles to stabilize the mandible and reduce forward movement of the condyle in the early opening phase.
3) Symptomatic treatment:
Patients with subluxation and dislocation suffer arthealgia and reyalgia.
Analgesic and NSAID drugs used.
Muscle relaxants and transquilizers are useful. An important of etenoid ex: methyl prednisolone.
(Long acting corticosteroid avoided leads to CT atrophy and weakening of collagenous tissue therefore increasing joint luxity.
4) Occlusal Treatment:
Occlusal disturbances like: curpol interferences and xlon occlusion due to missing teeth with loss of vertical support should be corrected to prevent the instability of the joint.
5) Other ultrasound:
Has been shown to promote in vitro collagen synthesis by human fibroblasts therefore this may be help in stabilizing the point in conjunction with isometric exercise.
Techniques of manual reduction:
Manual repositioning of the condyles is best performed with the patient seated upright in a chair with the back supported and in front of the standing clinician.
The clinician’s thumbs are wrapped in gauge and positioned over the second molars bilaterally.
The index fingers are placed securely under the inferior border on both sides of the mandible just anterior to the antegonial notches.
The patient is asked to relax or much as possible to allow the mandible to move anteriorly.
The posterior aspect of the mandible is depressed inferiorly while the chin is elevated anteriorly to depress the condyles. The mandible is manipulated to allow the condyles to move posteriorly and reposition themselves in the fossa.
In bilateral dislocation relaxation of the condyles can occur simultaneously.
Often reduction of one side results in the reduction of the other side.
- Reduction of a dislocation of several days duration of those that are complicated by severe muscle spasms can be facilitated by an injection of local anesthetics into the glenoid fossa.
The anesthetic agent blocks the sensory reflex mechanism of the joint. Thus reducing the muscle spasm produced by the dislocation and preventing the reflex spasm imitated by the manipulation procedure.
- Diazepam (valium) 10mg given orally / 1hr before / I.V. immediately before manipulation may help to facilitate manual reduction.
- More severe cases require reduction with the patient under GA and administration of muscle relaxant to permit reduction.
- Jaw immobilization with I.M.F. is usually necessary and also helpful in patient who experiences excessive pain.
Yurino’s method places the patient is a supine position without a pillow.
The patient is encouraged to relax completely while the operator stands near the patient’s head and holds the body of the mandible from the opposite side.
The patient is asked to open and close the mouth and the operator moves the mandible up and down in phase with the patients opening and closing movements.
The operator then locates the dislocated condyle with his thumb and simultaneously with the patients closing motion pushes it completely downward while moving the body of the mandible upward by this procedure the condyle moves over the articular eminence and ships into the fossa. In case of bilateral dislocation one side is reduced first.
The injection of sclerosing agents into the supporting ligaments into the joint.
Objective: is to produce fibrosis and tightening of the capsular ligaments thus limiting motion of the mandible and preventing subluxation and dislocations.
Ex: Sodium prylliate emulsion in oil.
Sodium tetraderyl sulfate
Alcohol, homogenous blood.
Disadvantages: Inability to predict the amount of limitation that will be produced.
It can be too little / too much
Complication of 7th nerve damage.
0.5ml solution, about 2 to 3 injections.
The injections were spaced 1 to 2 weeks apart the average t/t time was 1 month maxilla and mandible fixation avoid excessive opening.
Intermaxillary fixation (I.M.F.)
Limiting the oral opening by giving elastics total immobilization of the jaw for the period of 3 to 4 weeks gives rest to the joint.
Keep the patient on bioccid / soft diet.
The factor recosting reduction of a dislocation
- Normal tone in the muscles of mastication.
- Spasm in the muscles of mastication –
- Produced by a result of an abnormal position of the mandible and resultant soft tissue injury.
- Induced by attempts to reduce the dislocations.
- Displacement and wedging of the meniscus.
- Fibrous adhesions.
- Filling of the articular tissue with dense fibrous tissue.
- Surgical Treatment:
– The disorders of the TMJ non-surgical method will control the symptoms of the majority of patients.
It is prudent then to ensure that the patient has undergone adequate conservative treatment before recommending surgery.
It is also important that muscular and psychological factors are managed appropriately. If psychological disturbance may control indicative to the surgery.
The indications for surgery include a disassing recurrent dislocation and long standing dislocation not responsive to closed manipulations and other non surgical treatment.
Acute dislocation and habitual dislocation with significant psychologic influence are rarely indications for surgery.
A number of different surgical methods have been described:
There are three broad categories of procedures which are designed to limit:
- Procedures to limit translation.
- Anchoring procedures:
- Capsular placation.
- Flaps secured to the capsule.
- Autogenous and alloplastic slings between the condyle and zygomatic process.
- Securing the disk to the capsule and tragus cartilage anchoring the coronoid process to the zygoma.
- To eliminate blocking factors in the condylar path of closure / both.
- Combined procedures to eliminate blocking and limiting translation.
- Lateral pterygoid myostomy with diskectomy.
- Condylectomy – high condylectomy.
Procedures to limit translation:
Anchoring procedures reduce or eliminate the anterior or trantational motion of the condyle.
- a) Capsulorrhapy: Consists of shortening the capsule by removing a section and suturing it to make it tight.
“Rahn” used a 1x6mm de epidermized skin flap from the occipital region based on clinical periosteum trimmed and secured to the capsule to augment a capsullorrapy.
“Neiden” modified Rahn is procedure by using a temporal fascia flap is a some manner.
Morris sutured the capsule to the zygomatic process of the temporal bone to reduce laxity.
- b) Disk placation: can be either a complete / partial procedure.
In complete disk placation a full wedge of retrodiskal tissue is removed and the disk is repositioned by suturing the remaining retrodiskal tissue directly to the posterior ligament. The partial placation a small pH shaped wedge of tissue is removed to facilitate repositioning.
- c) Autogenous/alloplastic slings between the condyle and zygomatic process.
“Gordon” used fascia lata transplants secured through a vertical hole in the zygomatic process wear its base and another horizontal hole in the condyle anteriorly to the inhibit anterior movement of the condyle.
“Mertrill” modified this technique by utilizing wide Dorson sutures.
- d) Lateral pterygoid myotomy:
- Rationale of this procedure is to reduce/eliminate the muscular force thought to be responsible for pulling the mandible into the dislocated position.
- Condylar translation is reduced convexity.
- Roman first described this procedure for recurrent dislocation.
- Myotomy eliminates the action of the superior belly of the lateral pterygoid mucle.
- The upper half of the lower belly is severed at its infection to the condyle.
- “Laskin” reported that the lateral pterygoid muscle was detached and a short of silicone rubber was secured over the pterygoid fossa of the condyle to prevent reattachment.
Blocking / arthrocresis procedures to interface with translation are designed to create an obstacle to the condyle in its opening path.
- Soft tissue, 2) bony procedures.
The better increase the height of the articular eminence by osteotomies, bone grafts and metal implants.
- Soft tissue:
surgically creates a closed lock by the disk.
This procedure produces fixation of the disk in an anterior position (closed lock) the posterior ligament of the disk in released and the anterior attachment is preserved.
The disk is pulled anteriorly and inferiorly and is anchored vertically infront of the condyle by suturing it to the lateral pterygoid muscle inferiorly and to the capsule laterally.
Foged and others say that there is a loss of flattening of the articular eminence is patients with recurrent and habitual dislocation and they advocated the rebuilding of the eminence to create a block to condylar motion.
“Mayer”, resulted a 1.5µm segment of the zygomatic arch and grafted it into a furrow he created in the articular eminence.
Muscle on oblique osteotomy to increase the height of the articular tubercle bone of the tubercle and eminence was tilted inferiorly and anteriorly.
Eossere and Cautery:
Advocated the zygomatic arch is cut vertically infront of the joint and lowered.
Resistance to forward glide of the condyle is provided by a bony abutment placed directly anterior to the condyle and firmly attached to the zygomatic bone posteriorly.
Advantages: It nearly doubles the height of the articular tubercle.
“Morgen” restoring a flattened eminence when associated with subluxation and dislocation by using an eminence chrome cobalt prosthesis to create a blocking effect.
In repeated dislocation there is abnormal laxity of supporting ligaments and host the articular eminence. Create new eminence and block with a rib graft.
Eliminating blocking factors in the condylar path:
- To eliminate obstacles in the condylar path that may either trigger/ a dislocation / mechanically prevent reduction of the condyle into the glenoid fossa.
- A torn / displaced disk caught behind the condyle or a prominent articular eminence, may also or an obstacle to closure contributing to the condyle becoming stuck momentarily in subluxation prolonged dislocations. Two procedures are there:
- b. Diskectomy.
- Diskectomy / meniskectomy:
In the removal of the central avascular portion of the disk and the area of perforation through the posterior ligament.
Most difficult portion of the disk to remove in its medial subunion.
Menisectomy with replacement:
Autogenous, allogenic and olloplastic materials have all been need to replace the disk after menisectomy.
Autogenous – desuis, auricular cartilage, temporalis fascia/ temporalis muscle/ infections.
Allogenic – fascia, dura, and cartilage.
Dermal graft can be harvested free hand in the lateral thigh/abdomen.
An elliptical incision is made to exercise the full thickness graft with both epidermis/ dermis intact.
The graft molecule about 3 to 4mm. a 15 blade is used to remove the epidermal layer because graft tends to contract during harvesting and handling the piece of tissue exercised should be larger than the actual dimensions of the meniscal defect.
The skin graft is repositioned and sutured at the periphery.
- Is an operation currently used to correct recurrent dislocation.
- Relatively uncomplicated procedure.
- There is no study that supports the concept that the eminence blocks condylar reduction. Intact the eminence in patients with chronic subluxation and dislocation is flat.
- Exn of skull reveals that the eminence is actually quite flat anteriorly while the posterior slope may be steep.
- Acute spasm of elevator muscle keeps the condyle in the locked open position.
- First report by Myshong in 1951.
- Rationale – is to allow the condylar head to move forward and backward free of obstruction by the excision of the articular eminence instead of attempting to restrict the forward movement of the condylar head.
- Recurrent episodes of dislocations.
- Chronic hypermobility associated with severe pain.
- Irreversible TMJ pain associated with clicking / grafting.
- Internal derangement.
- Eminectomy exposes marrow and levalar a longbased area surface hemorrhage and enucleated friction between the articular surfaces and can lead to adhesions and limitations.
- Intracranial exposure of temporal lobe.
- Eminectomy is performed through the usual surgical approach to the TMJ without suturing the joint.
- After the zygomatic arch is identified a horizontal incision is made in the periosteum over the arch and is reflected inferiorly to expose the eminence.
- The osteotome directed inferiorly and medially in a surgically created groove and is tapped lightly to fracture the lateral tubercle and eminence.
- Frequent mistake is to remove only lateral tubercle and it may recurrence.
- Using a pneumatic bone file the medial aspect of the eminence is reduced and lateral area smoothened from contouring is done with a diamond hand file.
- Preoperative homologous taken to rule out pneumatization of the eminence.
- (T and MRI shows extension of the cancellous bone in the eminence so have to be taken to prevent intracranial exposure of the temporal lobe.
- The eminence must be recontoured as far medially as possible to ensure that adequate bone is removed.
- The foramen spinosum is located at the mesial aspect of the articular eminence. Injury to middle meningeal artery hemorrhage after eminectomy.
- Combined procedures to eliminate blocking and limit translation:
- Lateral pterygoid myotomy with diskectomy.
- Lateral pterygoid myotomy with diskectomy:
- First described by Roman.
- Restricts anterior gliding movement of the condyle and eliminates obstruction caused by the disk.
- Surgical procedure for recurrent dislocation.
- First described by Ward in 1952.
- painful joints with internal derangements.
- I/O approach to treat recurrent dislocation.
Entirely extra articular unilateral condylotomy is often sufficient for bilateral dislocation.
Condylotomy is an osteotomy through the condylar neck which is performed through an intraoral and intraoral apparatus.
Both procedures release the condyle and allow it to displace anteriorly and sag inferiorly.
The procedure reduce the strength of the lateral pterygoid muscle by shortening it while allowing it to remain functional.
Condylotomy is to reduce lateral pterygoid muscle pull to reduce conflicts of the condyle with the disk and eminence due to its inferior displacement.
Performed with “Gigli saw”.
The procedure was designed to induce displaced fracture through the condylar neck so that the condyle would be repositioned inferiorly and anteriorly.
This allows the condylar head to seat under the displaced meniscus and unload the posterior attachment.
An intraoral subsigmoid. Vertical osteotomy is performed and the patient is maintained in I.M.F. with notches for a 2 to 4 weeks period.
- Is a procedure in which the entire condyle is resected.
- Is a surgical approach to treat-ankylosis.
- Prepare the joint for a total alloplastic prosthesis costochondral graft.
- A complete condylectomy.
- High condylectomy.
- Complete condylectomy:
Of producing facial and occlusal deformity.
Lateral pterygoid muscle is sacrified allowing only rotational movement without translation.
The ramus is shortened producing in open bite deformity and retrusion of the mandible.
The blocking effect of the condyle on the disk/ eminence is removed in this procedure.
It can be considered a procedure that both restricts forward motion and removes blocking factors.
This operation is a host lost resort when other operations have failed/ in long standing dislocations.
Is performed through the standard indural approach used to identify the neck of condyle of the level of the sigmoid notch below the most inferior lateral capsular attachment. The condyle is sectioned with 1mm. pressure bur is used to make up at the level of the sigmoid notch. The cut is made completely through the lateral anterior and posterior surfaces but the lost section of medial cortical bone is preserved a T-bar osteotome is gently tapped and traveled to complete the condyles cut. While protection is provided the inferior maxillary artery which lies medial to the condylar neck.
- 7to 8mm of the entire condylar head is removed.
- Is a more conservative operation with preservation of most of the lateral pterygoid muscle.
- Low significant decrease in vertical height of the ramu.
- It is preferred over condylectomy and it will also eliminate conflicts with the disk and eminence.
- Scar formation and partial loss of lateral pterygoid muscle will limit movement.
- Condylectomy for ankylosis and protects joint placement and with chomoral grils grafting.
- In which osteotomy cut in at the base of the coronoid to prevent post surgical ankylosis.
- In case of ankylosis sectioning the condyle at a level below the ankylosis (at sigmoid notch) is advised before attempting to separate the ankylosis bone at the superior glenoid fossa margin.
- The treatment of hypermobility disorders painful hypertranslation subluxation dislocation should be approached in a careful and conservative manner.
- The surgeon should employ the simplest and most effective method with the least morbidity for a specific patient.
- It is also important that muscular and psychologic factors are managed appropriately.
- Principles of Oral and Maxillofacial surgery – vol. 3, Peterson.
- Surgery of the TMJ – David A. Keith.
- Color atlas of TMJ surgery – Peter D. Quinn.
- Oral and Maxillofacial surgery TMJ disorders – R.J. Fonseca.
- Anatomy for surgeons head and neck – Vol. I – W.H. Hollinshead.
- Text book of oral and maxillofacial surgery – Kruger.
- The role of local anesthesia in the reduction of longstanding dislocation of the TMJ. BJOMS, 1980; 18: 81-85.
- Articular eminectomy for recurrent dislocation. BJOMS, 1987; 25: 237-243.
- A new approach to the reduction of acute dislocation of the TMJ. A report of three cases, BJOMS 1987; 25: 244-49.
- Shortening of the temporalis tendon for hypermobility of the TMJ. J. Oral Surg. Vol. 76, July 1978.
- Miniplate eminoplasty: A new surgical treatment for TMJ dislocation. JOCMF Surg. 1993, 21: 176-178.
- TMJ disorders diagnosis and treatment – Kaplan and Arsael.