Temporo-mandibular Articulation

The two bones that form the Temporomandibular Joint (TMJ) are the cranial bone (specifically the squamous part of the temporal bone) and the mandibular bone.

The Temporomandibular Joint is a synovial joint, meaning it's a freely movable joint with a synovial cavity and articular cartilage.

The articular surface of the temporal bone in the TMJ is also known as the cranial component.

The TMJ is classified as a ginglymoarthrodial joint, meaning it allows for both hinge and gliding movements.

The articular eminence of the temporal bone is strongly convex from front to back (anteroposteriorly) and concave from side to side (mediolaterally).

In a fibrous joint, like the TMJ, fibrous tissue connects the bones.

The articular tubercle of the temporal bone serves as a point of attachment for the collateral ligaments that help stabilize the TMJ.

The condyle of the mandible is rounded from side to side (mediolaterally) and convex from front to back (anteroposteriorly).

The Temporomandibular Joint is classified as a discontinuous articulation, meaning the bones are not directly joined, but rather connected by a joint cavity.

The anterior articular area of the glenoid fossa in the TMJ is formed by the inferior aspect of the temporal squama (part of the temporal bone).

There are two Temporomandibular Joints in the human body, one on each side of the head.

The squamous part of the temporal bone articulates with the mandible in the Temporomandibular Joint.

The surface of the glenoid fossa in the TMJ is smooth and oval-shaped.

The Temporomandibular Joint provides a hinge or rotational movement in one plane, allowing for opening and closing of the jaw.

The mandible in the TMJ is broad laterally (sideways) and narrow medially (towards the midline).

The cavity surrounding the joint in the TMJ is called the synovial cavity, filled with synovial fluid that lubricates the joint.

The mediolateral diameter (side-to-side) of the mandibular condyle (the rounded part of the jawbone) is typically between 13 and 25 millimeters.

The posterior attachment of the articular disc in the TMJ divides into the inferior lamella (lower part) and superior lamella (upper part).

The primary function of the articular disc in the TMJ is to stabilize the joint, distribute forces, and allow for smooth movements.

The upper joint space in the TMJ, between the articular eminence and the articular disc, has an approximate volume of 1.2 milliliters.

The mandibulo-malleolar ligament is not a true ligament of the TMJ. This ligament does not exist in the TMJ.

The articular disc in the TMJ is biconcave (curved in both directions) and thicker in the anterior (front) part than in the posterior (back) part.

The central region of the articular disc in the TMJ is referred to as the central intermediate zone.

The collateral ligaments in the TMJ attach the articular disc to the lateral (outer) and medial (inner) poles of each condyle.

The articular disc in the TMJ originates from the mesoderm of the 1st pharyngeal arch during embryonic development.