Temporomandibular Joint (TMJ) PDF

Temporomandib ular Jointgf (TMJ) 1  Temporomandibular Joint The temporomandibular joint (TMJ) is a joint on each side of the head that allows for movement of the mandible for speech and mastication. A joint is a site of junction or union between two or more...

Temporomandib ular Jointgf (TMJ) 1  Temporomandibular Joint The temporomandibular joint (TMJ) is a joint on each side of the head that allows for movement of the mandible for speech and mastication. A joint is a site of junction or union between two or more bones. 2  Bones of Joint The TMJ has two sets of articulation, one on each side of the head: two temporal bones and two mandibular condyles 3  Bones of Joint The temporomandibular joint (TMJ) is the articulation between the temporal bone and the mandible The surface of one bone moves over the surface of another  Bones of Joint: Temporal Bone Follow along on the skulls The temporal bone is a cranial bone that articulates with the mandible at the TMJ by way of the disc of the joint The mandibular fossa or articular fossa is posterior to the articular eminence and consists of an oval- shaped depression on the temporal bone Posterior to the articular fossa is a sharper ridge, the postglenoid process. 5 6  Bones of Joint: Mandible The mandible is a facial bone that articulates with the temporal bone of the cranium. This articulation is accomplished by way of the disc of the joint working with the head of the knuckle-shaped part of the mandibular ramus. The part of the ramus involved in this articulation is the mandibular condyle, specifically its articulating 7  Bones of Joint Applegate EJ. The Anatomy and Physiology Learning System, ed 3. Elsevier, 2006 8  Joint Capsule A fibrous joint capsule completely encloses the TMJ The joint is supported by the joint capsule and several ligaments 9  Disc of Joint or Articular Disc The articular disc or meniscus or disc of joint, is a fibrous pad of collagen tissue, that is located between the two bones  Disc of Joint or Articular Disc The disc completely divides the TMJ into two compartments or synovial cavities: upper and lower Epithelium lines these cavities and secretes synovial fluid This allows the surfaces to rub over one another without irritation 11  Dissection Disc of Joint or Articular Disc The membranes lining the inside of the joint capsule secrete synovial fluid that helps lubricate the joint and fills the synovial cavities. Figure 5-4C 12  Structure The articular eminence is positioned anterior to the mandibular fossa and consists of a smooth, rounded ridge that is a ramp-shaped segment 13  Structure Posterior to the disc is the retrodiscal pad/tissue Composed of loose connective tissue supplying blood and nerves to the joint.  Ligaments Associated with Joint The mandible is joined to the cranium by ligaments of the TMJ. A ligament is a band of fibrous tissue that connects bones. Three paired ligaments are associated with the TMJ: 1. Temporomandibular 2. Stylomandibular 3. Sphenomandibular 15  Temporomandibular Joint Ligament The temporomandibul ar ligament is located on the lateral side of each joint forming a reinforcement of the lateral part of the joint capsule of the TMJ. The TMJ ligament prevents the condyle from being displaced to far inferiorly and posteriorly and 16 prevents lateral  Stylomandibular Ligament The Stylomandibular ligament is a variable ligament in the area that runs from the styloid process of the temporal bone to the angle of the mandible. It separates the parotid and submandibular salivary glands 17  Sphenomandibular Ligament The Sphenomandibula r ligament is not considered a part of TMJ -Helps control movement -Runs from angular spine of sphenoid to lingual becomes taut when mandible protrudes and can prevent diffusion of local anesthetic agent during inferior alveolar nerve block 18  Clinical Note: Sphenomandibular Ligament The sphenomandib ular ligament is a landmark for the administration of inferior alveolar block and is also involved in troubleshootin g the injection due to its location. 19 Figure 9-37 https://www.youtube.com/watch?v= mB468Jh9aAY&vl=en 20  Movement in TMJ The TMJ has two types of movement: Rotational Gliding As the teeth begin to separate, there is a rotational movement in the lower synovial cavity between the disc and the condyle below As the jaw opens farther, the rotational movement continues, but an additional anterior gliding movement also occurs  Gliding Movement Protrusion – anterior movement Retrusion – posterior movement 22  Rotational Movement Depression –lower the jaw Elevation – raise the jaw 23  Gliding and Rotational Movement Lateral Deviation – alternating protrusion and retrusion 24  Gliding and Rotational Movement Open the mouth = Protrusion and Depression Close the mouth = Retrusion and Elevation 25  TMJ Dysfunction (TMD) A client may have pathology associated with one or both of the TMJs or a temporomandibular disorder (TMD). They may experience chronic joint tenderness, swelling, and painful muscle spasms Also present may be difficulties of joint movement such as a limited or deviated 26 mandibular opening  Assessing the TMJ for TMD To palpate the joint and its associated muscles effectively, have the client go through all the movements of the mandible in relationship to the TMJ while bilaterally palpating the joint just anterior to the external acoustic meatus of each ear 27  TMJ Assessment This includes asking the client to open and close the mouth several times and then to move the opened jaw to the left, then to the right, and then forward 28  TMD Not all clients with TMD have abnormalities in the joint disc or the joint itself Most symptoms seem to originate from the muscles supporting the joint 29  TMJ Sounds Many will complain of clicking, popping or grinding (crepitus) in the TMJ yet have no other symptoms like pain. Popping or clicking occurs when the disc is pulled too far forward on opening If it pops on closing it is called a “reciprocal pop or click” On palpation you may notice the joint ‘jump’ If the joint jumps on one side, you may see the mandible deviate/shift to one side on opening Treatment includes: ultrasonography, 30  Disc Disengagement The cause of TMJ sounds may be the result of disc disengagement In constant anterior displacement of the disc, permanent damage may occur Treatment may require surgical intervention 31  Trismus Trismus: the inability to open the mouth normally 32  TMJ Problem: Subluxation An acute episode of TMD can occur when a client opens the mouth too wide, causing maximal depression and protrusion of the mandible, like when yawning or receiving prolonged dental care This causes subluxation or dislocation of both 33  TMJ Problem: Subluxation Happens when the condyle glides too far forward and moves too far anterior to the height of the articular eminence Muscles are trying to pull the jaw up and back but the articular eminence does not allow movement Contributing factors: deep condylar fossa, or 34  TMJ Problem: Bruxism Bruxism: teeth grinding Typically happens during sleep but some do it while awake Causes tired and sore TMJ, wearing down of teeth Treatment: Night guard, and relaxation medications (tranquilizers) 35  TMJ Problem: Arthritis Arthritis: Inflammation and deterioration of the joint Potentially caused by excessive wear of the joint Treatment option: Cortisone 36  TMJ Problem: Myofascial Pain Dysfunction (MPD) Myofascial pain dysfunction (MPD) syndrome, has increased pain at the TMJ due to muscle tension and spasm It is believed that MPD syndrome is a physical manifestation of psychological stress No primary disorder of the joint itself is present 37  TMD Most cases of TMD improve over time with inexpensive and reversible conservative treatments, including over- the-counter or prescription pain control, relaxation therapy, stress management, habit control, moderate muscle exercises, and orofacial myology