TMJ

The temporomandibular joint (TMJ) connects the mandible to the skull and is located bilaterally in front of the ears. It enables speech and mastication via complex coordinated movements.

The TMJ is composed of three main parts: the mandibular fossa, the articular eminence (both part of the temporal bone), and the mandibular condyle.

The TMJ allows for depression and elevation (up and down), lateral deviation (side to side), protrusion and retrusion (forward and backward) of the mandible.

Initial opening of the mandible involves the condyle rotating within the glenoid fossa, like a hinge.

The fibrous capsule and TMJ ligaments help restrict excessive lateral movements during wide opening, preventing the joint from dislocating.

The TMJ is surrounded by a capsule. This capsule attaches to various structures and houses the lubricating synovial tissue.

The articular disc is a biconcave structure located within the TMJ. It provides a smooth surface for movement between the condyle and the fossa.

The temporomandibular ligament, which is composed of an outer oblique and inner horizontal portion, helps stabilize the TMJ.

The stylomandibular ligament connects the styloid process to the angle of the mandible.

The sphenomandibular ligament links the sphenoid bone to the mandible.

Temporomandibular disorders (TMD) are a group of conditions affecting muscles and joints of the jaw.

Myofascial pain, a common type of TMD, is characterized by pain in the jaw muscles and surrounding areas.

Internal derangement involves a dislocated jaw or a displaced articular disc. It can cause clicking, popping, or locking in the jaw.

Degenerative joint disease, such as osteoarthritis or rheumatoid arthritis, can affect the TMJ.

Headaches, earaches, pain behind the eyes, jaw locking, clicking or popping sounds, changes in bite, limited mouth opening, pain during yawning or chewing can all indicate a TMJ disorder.

Trismus is a condition where the mouth can't open more than 35 mm. It can be caused by trauma, surgery, infection, or cancer treatments.

Non-invasive treatments for TMD include exercises, soft diet, heat application, medications, and bite guards.

Surgical options for TMD can include arthroscopy, joint surgery, or joint replacement, depending on the severity of the condition.

A dislocated jaw causes pain in the face, a crooked bite, and difficulty talking or closing the mouth.

Stretching exercises and soft diet help manage temporary or permanent Trismus.

Understanding TMJ anatomy and TMD is essential for managing patients in dental and oral health settings.

Accessory ligaments help limit side-to-side movements of the mandible, preventing excessive motion.

Rotation of the condyle within the glenoid fossa along a horizontal axis (hinge axis) is involved in the initial opening of the jaw.

The TMJ can also rotate along a frontal (vertical) axis and a sagittal axis, enabling other jaw movements.

The fibrous capsule of the TMJ functions to enclose the joint and provide stability during movement.

The articular eminence of the temporal bone acts as a guide during mandibular protrusion, preventing excessive forward movement.

The mandibular condyle, which is part of the mandible, articulates with the glenoid fossa and articular eminence, forming the TMJ.

A soft diet can help reduce strain on the jaw muscles and allow for better healing in cases of TMD.

The TMJ is subject to various disorders, including myofascial pain, internal derangement, and degenerative joint disease.