intro/anatomy of TMJ Flashcards
what is orofacial pain
Evaluation, diagnosis and treatment of:₁
1. Temporomandibular Joint Disorders (TMD)
2. Masticatory muscle pain
3. Cervical muscle pain
4. Neurovascular pain/headaches
5. Neuropathic pain (nerve dysfunction)
6. Obstructive Sleep apnea
7. Intraoral, intracranial & systemic disorders that cause facial pain
OF pain as a bridge
Bridges the gap between medicine and
dentistry
causes of OF
trauma or medical disorders
trauma to jaw
- Sports Injuries
- Motor Vehicle Accidents
- Domestic Abuse
- Clenching and Bruxing
medical dx leading to OFP
Arthritis
Migraine Headaches
Nerve Dysfunction
Viruses/infections
Muscle Disorders
Neurological Disorders
common jaw symptoms
Jaw pain
Limited mouth opening
Clicking and grinding noises
Difficulty with normal daily activities (i.e. eating, talking, opening)
common TMDs
- Disc displacement
- Inflammatory disorders
- Arthritis
- Masticatory muscle disorder
when was OF recognized as special
2020
professional associations of OFP
American Academy of Orofacial Pain (AAOP)
American Headache Society
American Pain Society
International Headache Congress
why is OFP a special
To help people in pain
To help diagnose difficult disorders
To help patient psychologically and to give
the patient a sense of control over their pain
To improve sleep apnea symptoms which can
save the patient’s life
Patients are typically very appreciative of your
assistance and their quality of life is
significantly improved
what type of joint is the TMJ? what does this mean?
The TMJ is a ginglymoarthrodial joint with hinging or rotation movements in one plane (ginglymoid joint) & gliding or translation movements in another plane (arthrodial joint)
The condyles/jaw move synchronously- both sides move together (pain can be opposite of trauma)
Temporomandibular Joint
Two of?
Articulation between?
The mandibular condyle fits into?
The articular disc seperates?
Temporomandibular Joint
Two of the most complex joints in the body.
Articulation between the cranium & mandible.
The mandibular condyle fits into the mandibular (glenoid) fossa
The articular disc separates these 2 bones from direct contact
TMJ Capsule
A fibrous capsule contains the synovial fluid, limits its motion and maintains the
relationship between the joint components.
Temporomandibular Joint (TMJ) as a synovial joint
Is a Synovial joint
Synovial fluid(synovia) roles?
Synovial fluid is secreted by? how much present?
Articular Disc separation?
Is a Synovial joint
Synovial fluid(synovia) transports nutrients to & waste products from the articular surfaces & lubricates joint
Synovial fluid is secreted by the membrane lining the synovial joint and there is approximately 1cc in each compartment of the joint spaces
Articular Disc separates the condyle & mandibular fossa from direct contact & divides joint into superior and inferior joint spaces
why would these ondyles be less mobile
elongated articular eminences
label
Functions of Disc
- Distributes loading forces
- Decreases wear
- Stabilizes condylar movement
Disc
1. Articular portion is composed of?
2. Has some ability to?
3. Is devoid of?
4. The posterior attachment of the disc is?
Disc
1. Articular portion is composed of dense fibrous connective tissue NOT cartilage
2. Has some ability to repair itself
3. Is devoid of nerves or blood vessels in the intermediate zone which articulates with the superior aspect of the condyle during translation
4. The posterior attachment of the disc is highlyvascularized and innervated
histology slide of TMJ
disc/ posterior attatchment histo
- Dense, fibrous connective tissue
- Non-vascular in center
- Non-innervated in center
B. Posterior attachment (Retrodiscal Tissue)
1. Loose, vascular, connective tissue (contains collagen fibers, adipose tissue, elastin, arteries & a venous plexus)
2. Richly innervated by auriculotemporal nerve
The articulating surfaces of tmj are lined with?
The articulating surfaces are lined with dense
fibrocartilage (instead of hyaline cartilage) which
allows for a greater ability to heal
Articular Cartilage
defined?
Plays an important role as?
Research suggests that compressive loading is highest where?
Composed of?
A thin layer of cartilage covers the articulating surface of the bones.
Plays an important role as a stress absorber during function.
Research suggests that compressive loading is highest in the anteromedial region of the condyle (1).
Composed of cells and extracellular matrix (i.e. collagens & proteoglycans).
discal ligaments
Allow the disc to move in?
Discal ligaments may become? why?
Allow the disc to move in anterior-posterior direction during condylar translation.
Discal ligaments may become inflamed & painful because they are vascularized and innervated.
capsular ligaments
function?
Attach the disc to the condyle on the medial & lateral surfaces
Allow the disc to rotate on the condyle during condylar translation
encompass the entire TM joint retaining the synovial fluid and resist medial/lateral/inferior forces that might dislocate the articular surfaces.
extracapsular ligaments role
Ligaments passively limit joint movement: Sphenoman and styloman ligaments
Aa supplying mid face
maxillary
TMJ vascular supply
- Superficial temporal artery
a) Transverse facial - Maxillary artery
a) Deep auricular
b) Masseteric
c) Posterior deep temporal
TMJ nn supply
Auriculotemporal (V3) nerve
Masseteric nerve
what is normal disc position
11-12 o’clock position of condyle with posterior thick band
what is the MC disc displacement
medial and anterior, can lead to clicking
is clicking always tx?
no, only if pain present
TMJ translation
where does tmj rotation occur
Rotation occurs
between inferior
disc surface and
condyle
where does tmj translation occur
Translation occurs
between the superior
disc surface and fossa
when mouth is fully open where is condyle
Condyle reaches mid-
articular eminence
what happens when pt is not centered on pano
asymmetry
path?
no WNL
path?
no, considered remodeling
flattening and cortical thickening of the antero- superior surface of the condylar
head and glenoid fossa
what is likely happening
arthrhitis, cystic bone changes and possible osteophyte formation
arthrhitis open mouth CT
may be Bone on bone contact with decreased joint space indicating severe arthritis, possible MRI to determine state of disc
what is happening here?
arthirhits
Masticatory Muscles
- Masseter
- Medial pterygoid
- Temporalis
- Lateral pterygoid
- Digastric muscle
Masticatory Muscles
1. Skeletal muscles which provide movement of?
2. Functional behaviors:
3. Nonfunctional (parafunctional) behaviors:
4. Innervation:
Masticatory Muscles
1. Skeletal muscles which provide movement of the TMJ’s
2. Functional behaviors: talking, chewing, and swallowing
3. Nonfunctional (parafunctional) behaviors: bruxism, clenching, or empty-mouth chewing movements (i.e. tardive dyskinesia, orofacial dystonias)
4. Innervation: V3 (Mandibular Nerve)
masseter mm functions
SUPERFICIAL MASSETER: Elevates the mandible (closes the jaw)
DEEP MASSETER: Retrudes the mandible
temporalis actions
medial pterygoid mm actions
lateral pterygoid actions
digastric mm action
Temporomandibular Disorders (TMD)
A collective term that includes a number of clinical problems involving the masticatory muscles, TMJ & associated structures which are identified as the major cause of non-dental pain in the orofacial region:
1. Musculoskeletal Disorders
2. Articular Disc Disorders
3. Inflammatory & non-inflammatory Disorders
