Temporomandibular Joint

TEMPOROMANDIBULAR JOINT

Batallones, Amery Rose Galeno, Chris Carlo

Saunar, Maurice CheekzTalag,Bryan Matthew

Ursal, Alyssa MaeVillacorta, Aimee Carmina

INTRODUCTION TO TMJ(FUNCTION, FEATURES, CLASSIFICATION OF JOINTS)

Prepared by Chris Carlo M. Galeno

Temporomandibular Joint

• Craniomandibular Joint

• Articulation between the condylar head of mandible and the anterior part of the glenoid fossa of two temporal bones.

• Frequently termed as TMJ

Features of TMJ

• Coordinated movements of the right and left joints are complex and usually are controlled by reflexes.

• The maxillae and mandible carry teeth whose shape and position greatly affect the most closed portions of mandibular movements.

• Articulating surface of the TMJ is not formed of Hyaline cartilage but of a sturdy avascular fibrous layer.

• Only synovial joint in the human body with an articulating disc which is present between the joint surfaces of cranium and mandible which makes the TMJ a double joint.

Classifications of Joints

• Fibrous Joint

• Cartilaginous Joint

• Synovial Joint


• Fibrous joints

• Suture- articulation by processes and indentation interlocked together

• Gomphosis- articulation by insertion of a conical process into a socket

• Syndesmosis- united by interosseous ligament


• Cartilaginous joints

• Primary Cartilaginous

• Secondary Cartilaginous


• Synovial joints– According to number of axes in which the bones involved can move:

• Uniaxial• Biaxial• Multiaxial or Polyaxial

– According to the shapes of the articulating surface:• Planar• Ginglymoid• Pivot• Condyloid• Saddle• Ball-and-socket

Fibrous: A-syndesmosis (tibiofibular), B-suture (skull). Cartilaginous: C-symphysis (vertebral bodies), D-synchondrosis (first rib and sternum). Synovial: E-condyloid (wrist), F-gliding (radioulnar), G-hinge or ginglymus (elbow), H-ball and socket (hip), I-saddle (carpometacarpal of thumb), J-pivot (atlantoaxial).

Hilton’s Law

• The principle that the nerve supplying a joint also supplies both the muscles that move the joint and the skin covering the articular insertion of those muscles.

Type of joint of Temporomandibular Joint

• Synovial joint

• Described as synovial sliding-ginglymoid joint articulation

• Rotational movements• Translational movements

Innervation and Vascularization

• Sensory innervation from auriculotemporal and masseteric branches of mandibular branch of the trigeminal nerve

• Branches of the external carotid artery, predominately the superficial temporal branch, deep auricular artery, anterior tympanic artery, ascending pharyngeal artery, and maxillary artery

Specific Mechanics of Proprioception

• Ruffini endings

• Pacinian corpuscles

• Golgi tendon organ

• Free nerve endings

ANATOMY AND HISTOLOGY OF THE STRUCTURES INVOLVED IN THE TMJ

Prepared by: Maurice Cheekz A. Saunar

Anatomy of TMJ•Condyle of the Mandible•Mandibular Fossa/Glenoid Fossa/Temporoman-dibular Fossa

•Articular Surface Proper:

Articular DiscArticular Capsule

Ligaments

•Lateral Temporomandibular Ligament

•Sphenoparietal Ligament

•Stylomandibular ligament

•Stylohyoid Ligament

Synovial Tissue

-filled with Synovial Fluid

Function:-Lubricant

- Nutrition

- Regulatory

HISTOLOGY OF THE COMPONENTS OF TMJ

Condyle of the Mandible

• Composed of fibrous tissue

• Cells: Chondrocytes

Articular Disk

• Composed of fibroelastic connective tissue

Articular Capsule

Articular Tubercle

Fetal and Adult TMJ

DEVELOPMENT OF THE TMJPrepared by Aimee Carmina Villacorta

• Involves the development of the following structures– Mandible– Glenoid fossa– Condyle– Articular disc– Upper and lower joint cavity

Mandible

• Meckel’s Cartilage• Begins at week 6 to 7

• At week 12 of gestation:– temporal/ glenoid blastema

• Ossifies and becomes glenoid fossa – condylar blastema

• Becomes the condylar cartilage

• Clefts are formed– lower joint cavity– upper joint cavity

1. Primitive articular disc

2. Upper cleft3. Lower cleft4. Temporal

blastema5. Condylar

blastema

4

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1. Glenoid fossa2. Upper joint cavity3. Articular disc4. Lower joint cavity5. Condyle

Prepared by: Talag, Bryan Matthew E.

MUSCLES OF MASTICATION

Masseter

- Thick- Quadrilateral muscle- Superficial and deep portion

Masseter: Superior portion

Origin: thick, tendinous aponeurosis from the zygomatic process of the maxilla

Insertion: angle and lower half of the lateral surface of the ramus of the mandible

• its fibers pass downward and backward

Masseter: deep portion

• Smaller and more muscular in texture• Downward and forward• Partly concealed• Origin: posterior third of the lower border and

from the whole of the medial surface of the zygomatic arch

• Insertion: the upper half of the ramus and the lateral surface of the coronoid process of the mandible

Masseter

Temporal Muscle

• Broad• Radiating• Side of the head• Origin: Whole of the temporal fossa (except that

portion of it which is formed by the zygomatic bone)• Insertion: the medial surface, apex, and anterior

border of the coronoid process, and the anterior border of the ramus of the mandible nearly as far forward as the last molar tooth

Temporal muscle

Lateral pterygoid muscle

• A.k.a. pterygoideus externus or external pterygoid muscle

• Short• Thick• Conical• Upper and lower part

– Common insertion: depression in front of the neck of the condyle of the mandible, and into the front margin of the articular disk of the temporomandibular articulation.

Lateral pterygoid: Upper part

• Origin: lower part of the lateral surface of the great wing of the sphenoid and infratemporal crest

Lateral pterygoid: Lower part

• Origin: lateral surface of the lateral pterygoid plate

Lateral pterygoid

Medial pterygoid muscle

• A.k.a. pterygoideus internus or internal pterygoid muscle• Thick• Quadrilateral• downward, lateralward, and backward• Origin: medial surface of the lateral pterygoid plate and the

grooved surface of the pyramidal process of the palatine bone– Has a second slip of origin

• lateral surfaces of the pyramidal process of the palatine and tuberosity of the maxilla

• Insertion: lower and back part of the medial surface of the ramus and angle of the mandible, as high as the mandibular foramen

Medial pterygoid

Nerve supply

Mandibular branch of the trigeminal nerve

Action

• Temporalis, Masseter, and Medial pterygoid raise the mandible against the maxillæ with great force.

• Lateral pterygoid protrodes the mandible and the inferior incisors projectes in front of the upper antagonist– draw forward the condyle and articular disk – assists in opening the mouth– assisted by the Medial pterygoid

The posterior fibers of Temporalis retracts the mandible When Medial and Lateral pterygoid of one side act, the

corresponding side of the mandible is drawn forward while the opposite condyle remains comparatively fixed, and side-to-side movements. Such as occur during the mastication of food, take place.

SummaryMuscles of MasticationMuscle Origin Insertion Nerve Supply ActionMasseter Zygomatic arch Lateral surface

ramus of mandible

Mandibular division of

trigeminal nerve (V3)

Elevates mandible to occlude teeth

Temporalis Floor of temporal fossa

Coronoid process of mandible

Anterior and superior fibers elevate mandible: posterior fibers retract mandible

Lateral pterygoid(two heads)

Greater wing of sphenoidLateral pterygoid plate

Neck of mandibleArticular disc

Pulls neck of mandible forward

Medial pterygoid(two heads)

Tuberosity of maxillaLateral pterygoid plate

Medial surface of angle of mandible

Elevates mandible

Mandibular Positions

• Postural Position of Mandible

• Centric Occlusal Relation

• Right Lateral Occlusal Relation

• Left Lateral Occlusal Relation

• Protrusive Occlusal Relation

MOVEMENTS OF THE TMJPrepared by Alyssa Mae Ursal

Mandibular Positions• Postural Position

of Mandible

Free Way Space or

Vertical Dimension

of Rest


• Postural Position of

Mandible

• Centric Occlusal

Relation

• Right Lateral Occlusal

Relation

• Left Lateral Occlusal

Relation

• Protrusive Occlusal

Relation


• Postural Position of

Mandible

• Centric Occlusal Relation

• Right Lateral Occlusal

Relation

• Left Lateral Occlusal

Relation

• Protrusive Occlusal

Relation

Mandibular Movements

• Classification:

Border Movements

Intraborder Movements

Contact Movements

Free Movements


• Right Lateral Movement

• Left Lateral Movement

• Protrussive Movement

• Retrussive Movement• Bennett Movement


• Right Lateral Movement

• Left Lateral Movement

• Protrussive Movement

• Retrussive Movement

• Bennett Movement

Envelope of Mandibular Motion (by

Posselt)Lateral View

Superior View

Frontal View

CLINICAL CONSIDERATIONSPrepared by Amery Rose Batallones

Clinical Considerations

• Bruxism • Arthritis• Fractures • Structural Changes• Disharmony in the

relation of teeth and the TMJ

Clinical Considerations• Myofacial Pain

Dysfunction Syndrome

• Luxation or Dislocation of Temporomandibular Joint

• Ankylosis• Aplasia• Hyperplasia• Hypoplasia

Thank you!

Temporomandibular Joint

Education

Transcript of Temporomandibular Joint