TMJ Disorders

TMJ DisordersDr Saikat SahaDepartment Of Oral & Maxillofacial Surgery

ContentsIntroductionEpidemiologyEtiologyClassificationClinical featuresRadiological features Histopathologic featuresTreatment

EpidemiologyEpidemiologic studies 60-70% 20-40 years.

EtiologyMultifactorial:Parafunctional habitsStressTrauma

Abnormal maxillo-mandibular relationships. Rheumatic / musculo-skeletal disorders. Poor general health and unhealthy lifestyle. Anatomy

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Normal histology of TMJ

Classification(Etiology) I. Developmental AplasiaHypoplasiaHyperplasia

II. Traumatic AnkylosisInjuries of the articular disk

III. Fractures of the condyleIV. Inflammatory ArthritisRheumotoid arthritisOsteoarthritisV. NeoplasticVI. Extra-articular disturbancesVII. Temporomandibular joint syndrome (TMD)TMD secondary to myofacial pain and dysfunction (MPD)TMD secondary to true articular disease.DEVELOPMENTAL DISTURBANCESAplasia of the mandibular condyleUnilateral / bilateral. Rare C/FAssociated-- absent external ear ,under developed ramus / macrostomia. Facial asymmetryTreatmentOsteoplastyOrthodontic appliancesCosmetic surgeryHypoplasia of the mandibular condyle:Under development / defective formation Congenital hypoplasiaIdiopathic Characterized by uni / bilateral under development of the condyle

Acquired hypoplasiaForceps deliveries External traumaX-ray radiationInfectionC/f:Depends Degree of malformation. AgeDurationUnilateral

Limited lateral movementsMidline shift Lack of downward and forward growth of the mandible Arrest of the chief growth center of the mandible i.e., condyle.Treatment & prognosis:Cartilage / bone transplantsUnilateral and bilateral osteotomyHyperplasia of the mandibular condyle:

Rare unilateral enlargement of the condyle Causes: -Obscure -Mild chronic inflammation.C/f: Elongation of the face deviation of the chin away from the affected side. Enlarged condylemay or may not be painfulsevere malocclusion

R/F:Elongated neck and enlarged condylar head

Treatment and prognosis:Condylectomy Orthognathic surgery Resection of condyle

Condylar hyperplasiaBifid condyleDouble headed.Medial & lateral head. /Anterior & posterior head.Etiology:Uncertain.Traumatic in origin.Abnormal muscle attachmentC/F:UnilateralAsymptomaticPop or click of TMJ R/F:Bilobed appearance

Asymptomatic no treatment necessary.

Histologic section of bifid condyle

TraumaticLuxation and subluxation Dislocation of the TMJ Luxation of the joint SubluxationLuxation acute, due to a sudden traumatic injury resulting in the fracture of the condyle. Yawning / wide opening of mouth

Unilateral condylar dislocation

Bilateral condylar dislocation

Luxation & SubluxationC/f:Sudden locking and immobilization of the jaws.

Prolonged spasmodic contraction of the temporal, internal pterygoid and masseter muscles. Luxation & SubluxationTreatment:Relaxation of the muscles and then guiding the head of the condyle under the articular eminence into its normal position by an inferior and posterior pressure of the thumbs in the mandibular molar area.

AnkylosisFusion of head of the condyle temporal bone.Etiology:Idiopathic Traumatic injuriesInfectionRheumatoid arthritisAnkylosisC/f:1st decadeBefore 10 yearsM = FUnilateral /BilateralIn ability to open the jawsPain, tenderness and malocclusion

Unilateral ankylosis

AnkylosisIntra-articular ankylosisExtra-articular ankylosis-Destruction of the meniscus-Flattening of the mandibular fossa thickening of the head of the condyle -narrowing of the joint space-Fibrous adhesionExternal fibrous / osseous encapsulation.AnkylosisR/F:Abnormal / irregular shape of the head of the condyleTreatment:Surgical osteotomy / removal of section of bone below the condyle.Fibrous ankylosis can be treated by functional methods.

Injuries of the articular diskMalocclusionLoss of adaptation of the disk to the condyle.Precipitating factorsBlow / fallRheumatoid arthritisC/f:FemalesYoung adults frequently affected.Pain, snapping or clicking and crepitation. Transient / prolonged locking of the jaw may occur.

Injuries of the articular diskNormal disc position

Anterior disc displacement Injuries of the articular disk

Injuries of the articular diskR/F:No +ve findingsTreatment:Immobilization Menisectomy / surgical removal of the disk.Fractures Condylar fracture:Traumatic injuryLimitation of motionPain and swellingDisplaced anteriorly and medially into the infratemporal regionSurgical reduction

Unilateral Bilateral INFLAMMATORY DISTURBANCES Arthritis.3 types :Arthritis due to a specific infection.Rheumatoid arthritis.Osteoarthritis / degenerative joint disease.UncommonNeisseria gonorrhea, Str, Staph. Pneumococci, tubercle bacilli, H. influenzaeDirect spread of a local infection or blood stream / lymphatic metastasis.C/F:- Severe pain in the joint.Extreme tendernessHealing results in ankylosis.H-P Destruction articular cartilage and articular disc.Obliteration of joint space by the development of granulation tissueTransforms into scar tissue.Rx:Antibiotics in the acute phase Meniscetomy / condylectomy is advocated in the advanced cases.Rheumatoid arthritisChronic autoimmune disorder non-suppurative inflammatory destruction of the joints.Etiology: UnknownCross reaction of antibody against microorganisms deposited in the synovial membrane.A reactive macrophage laden fibroblastic proliferation from the synovium creeps onto the joint surface.Releases collagenases & proteasesDestroys the cartilage & boneTMJ involvement 20%

C/F:M:F = 1:3M = 25-30 yrs;F = 35-45 yrs Early stages manifestsRheumatoid arthritisPain, swelling and stiffness joint Clenching the teeth on one side produces pain of contra lateral joint. Destruction of condylar head receding chin & malocclusion

R/F:Flattened condylar headAn irregular surface of temporal fossaAnterior displacement of the condyleHigh resolution CT erosions of the condyle & glenoid fossae.H-P :Hyperplasia of synovial lining cells Hyperemia, edema and inflammation of the synovial tissues diffuse infiltration of chronic inflammatory cells into the articular architecture.

destruction of articular surface of the condyle.Invasion of the cartilage and its replacement by granulation tissue. Perforation of meniscus

Lab findings:80% of patients rheumatoid factorANA detected in 50%ESRMild anemia

Rx & Prognosis:Anti-inflammatory drugsCorticosteoids.Surgical interventionOsteoarthritisDisorder of articular cartilage, subcondral bone with secondary inflammation of the synovial membraneEtiology: unknown.GeneticAging process.Chronic microtrauma Primary above 50 yrs & asymptomaticSecondary due to trauma, metabolic diseaseC/F: Unilateral pain over the condyle & over muscles of masticationLimitation of mandibular opening Crepitus and stiffness Deviation of mandible towards painful sideR / F:Obliteration of the joint spaceSurface irregularities and protruberancesFlattening of the articular surface.Radiolucent subchondral cystsOssification within the synovial membrane

H-P /F:Degeneration of cartilage cells infiltration of chronic inflammatory cellsLoss of osteocytes fatty degeneration & necrosis of the marrowLarge degenerative space beneath the articular cartilage (Subchondral cysts)

Rx:NSAIDs, heat, soft diet, rest and occlusal splintsArthroplastyOrofacial physiotherapy.

NEOPLASTIC Neoplasms and tumor-like growths, benign and malignant, may involve the TMJ. Etiology: UnknownFrom embryonic mesenchymal remnants of synovium.That become metaplastic, calcify, break off into the joint spaceChondromas, osteomas and osteochondromas are common benign tumors.

Osteochondroma bone capped with cartilage and dense collagenous tissue

CT scan and arthroscopy is necessary for accurate diagnosis.Rx:Conservative and surgical removal of involved synovium and articular disk.

EXTRA-ARTICULARA variety of extraarticular disturbances may manifest themselves clinically as TMJ problems.Impacted molar teethSinusitis & Middle ear diseaseInfratemporal cellulitisNeuritis of the 3rd division of the trigeminal nerve.Odontolgia.Overclosure of the mandible due to severe dental attrition.Costens syndrome.TEMPORO MANDIBULAR JOINT SYNDROME Most common cause of facial pain after toothache.TMD can be classified broadly as:TMD secondary to myofacial pain and dysfunction (MPD).TMD secondary to true articular disease Etiology: Tissue injuryPhysical stress Bruxism and day time jaw clenching in a stressed and anxious person.Psychological & behavioural abnormalitiesPoor nutritional statusGenetic predisposition

DIGAMMATIC RERESENTATION OF ETIOLOGY OF MPDS PSYCHOPHYSIOLOGIC THEORY OF MPDS(Modified by LASKIN in 1969)

C /F:Constant diffuse unilateral painSevere in the morning and worsens as day progressesRadiates to cervical region, shoulders and backLimitation of jaw movement Deviation to the affected siteVII. TEMPOROMANDIBULAR JOINT SYNDROME (TM disorder)Cl / Ft:Tenderness in MMAngle of mandibleAnterior temporal region & coronoid aspectRx:Physiotherapy moist heat, TENS, Aucpressure, Acupuncture.Behavioural and relaxation techniquesOcclusal splint therapyNSAIDs, Muscle relaxants

2. True intra-articular disease :Disk displacement disorder.Chronic recurrent dislocations.Degenerative joint disorders.Ankylosis.Infection

Etiology:Malocclusion.Jaw clenching.Bruxism.Personality disordersIncreased pain sensitivity.Stress and anxiety.

C/F:Affects young woman aged 20-40 yrs.M:F 1:4.In TMD pain is unilateral associated with clicking, popping and snapping sounds.Limited jaw opening due to pain / disk displacement.Associated with chewing and may radiate to head.Treatment & Prognosis:1. Self limiting.2. Conservative treatment involving self care practices.Rehabilitation aimed at eliminating muscle spasms.3. NSAIDs Prognosis is good.

Investigations TMJTMJ imaging Panoramic radiographsTranscranial viewTranspharyngeal viewTransorbital viewReverse Townes viewSubmento-vertex (SMV) viewConventional tomographyArthrography

Computed tomography (CT)Magnetic resonance imaging (MRI)ArthroscopyBone scanReferencesShafers Textbook of Oral Pathology. 5th edition.Neville: Oral & Maxillofacial Pathology. 2nd edition.Jaffery P. Okeson Management of Temporomandibular disorders and occlusion.Martin S. Greenberg, Michael Glick Burkits oral medicine and diagnosis.Franklin C.D.: Pathology of the temporomandibular joint. Current Diagnostic Pathology (2006): 12, 31-39.