H&n Temporomandibular Joint

Front 1

Temporomandibular Joint

Back 1

• A.K.A TMJ

• A joint on each side of the head that allows for movement of the mandible for speech and mastication.

• Innervated by: Mandibular Nerve (or division) of the fifth cranial or trigeminal nerve

•Blood Supply: Branches of the External Carotid Artery

Front 2

Bones of the TMJ

Back 2

• 2 Temporal Bones
- Articular Eminence
- Articular Fossa
- Postglenoid Process

•2 Mandibular Condyles

Front 3

Back 3

Squamous Part of the Temporal Bone

Front 4

Back 4

Zygomatic Process

Front 5

Back 5

Articular Eminence

Front 6

Back 6

Articular Fossa

Front 7

Back 7

Postglenoid Process

Front 8

Back 8

Mandibular Condyle
• Part of the ramous involved in articulation with the temporal bone by way of the disc of the joint.

Front 9

Back 9

Joint Capsule

• Fibrous joint that completely incloses the TMJ.

Front 10

Back 10

Articulation Disc

• Located b etween the temporal bone and mandibular condyle.

• Allows articulation between the two bones.

• Completely divides the TMJ into compartments, aka the Upper Synovial Cavity and Lower Synovial Cavity.

• Filled with synovial fluid secreted by membranes lining the inside of the join capsule.

Front 11

Back 11

Temporomandibular Ligament

• Located on the lateral side of each joint forming a reinforcement of the lateral part of the joint capsule of the TMJ.

• Prevents the excessive retraction or moving backwards of the mandible, a situation that might lead to TMJ problems.

Front 12

Back 12

Sphenomandibular Ligament

• Not strictly considered part of the TMJ

• Located on the medial side of the mandible, some distance from the joint.

• Landmark for the administration of inferior alveolar block and is also involved in troubleshooting the injection due to its location.

Front 13

Back 13

Stylomandibular Ligament

• Variable ligament formed from thickened cervical fascia in the area.

• Becomes taut when the mandible is protruded.

Front 14

Back 14

Articular Eminence

Front 15

Back 15

Inferior Head of the Lateral Pterygoid

Front 16

Back 16

Postglenoid Process

Front 17

Back 17

Superior Head of the Lateral Pterygoid

Front 18

Back 18

Inferior Head of the Lateral Pterygoid

Front 19

Gliding Movement of the TMJ

Back 19

• Occures mainly between the disc and the articular eminence of the termporal bone in the upper synovial cavity, with the disc plus the condyle moving forward or backward, down and up the articular eminence
- Allows the lower jaw to move forward or protrude- involves the bilateral contraction of both the lateral pterygoid muscles.
- Allows the lower jaw to move backward or retract- involves the contraction of the posterior parts of both temporalis muscles.

Front 20

Rotational Movement of the TMJ

Back 20

• Occures mainely between the disc and the mandibular condyle in the lower synovial cavity with the axis of the rotation of the disc plus the condyle being transverse.
- Allows the lower jaw to depress - involves the lateral pterygoid, temporalis, suprahyoid, and mylohyoid muscles.
- Allows the lower jaw to elevate - involves the masseter, temporalis, and medial pterygoid muscles.

Front 21

TMD

Back 21

• Temporomandibular disorder

• patient may experience chronic join tenderness, swelling, and painful muscles spasms.

• may incluse difficulties of joint movement, or a limited or deviated mandibular opening.

• Can cause Subluxation, or dislocation of both joints.
• Can cause Trismus, or inability to normally open the mouth.