24- Joints and TMJ Flashcards
What does the articulatory system consist of?
- The hinge (TMJ)
- The motors (Muscles)
- The contacts
What are the 3 zones of the fibrous disc?
PB = posterior border IZ= Intermediate border AB = Anterior border
What are the three layers that lie behind the fibrous disc
- Superior retrodiscal lamina (elastic)
- Retrodiscal fat pad
- Inferior retrodiscal lamina (collagen)
What is the major muscle in TMD?
Lateral pterygoid as its superior portion is attached to the head of the condyle and the articular disc
Where is the temporalis origination and insertion?
Originates from the articular eminence and inserts onto the coronoid process of the mandible
Which muscle elevates and retracts the mandible?
Temporalis
Which muscle Elevates and protrudes the mandible?
Lateral pterygoid
Which muscles depress the mandible?
Gravity
- digastric
- geniohyoid
- mylohyoid
What are the 3 different types of definitions of centric relation?
- anatomical
- geometrical
- physiological
What is the anatomical definition of centric relation?
position of the condylar head when fully seated in the glenoid fossa
What is the geometrical definition of centric relation?
by means of posselts envelope, anywhere between R and RCP, (mandible just rotating)
What is the physiological definition of centric relation?
Position where the muscles are doing the least amount of work
What does RCP stand for?
Retruded contact position
What does ICP stand for?
Intercuspal position
What does E stand for?
Edge to edge position of incisors
What does Pr stand for?
Maximum protrusion
What does T stand for?
Maximum translation of condylar head/maximum mandibular opening
What does R stand for?
Maximum mandibular opening with the condylar heads still in glenoid cavity
What type of things would you record on the occlusion record?
- Skeletal base relationship
- Angle relationship
- First tooth that touches central relation
- difference in RCP and ICP
- canine guidance? group function?
What are the 3 main categories of temporomandibular disorders?
- Myalgia/myofascial pain
- Disc displacement
- Joint degeneration
What is myalgia/myofascial pain?
Report of pain or ache in the jaw, temples, face, preauricular area or inside the ear. PLUS this pain can be felt on palpation of one of the major muscles of mastication
What are the 2 types of disc displacement?
- With reduction
2. Without reduction
What does disc displacement with reduction mean?
- The disc is displaced anteriorly but reduces back into place making a clicking sound
What does disc displacement without reduction mean?
Disc is displaced anteriorly but does not return back to normal
What is joint degeneration?
Degenerative disorders of the join in which joint form and structure are abnormal e.g. arthrosis
What type of model of illness is TMD described as?
Biopsychosocial model of illness
What is bruxism
A parafunction which involves grinding/clenching of the teeth
What are the 2 types of bruxism?
Wake bruxism
Sleep bruxism
What is wake bruxism?
Habit in response to anxiety
How do we identify sleep bruxism?
- sleep study
- third party witness
- cheek ridging
- tooth wear
- tongue scalloping
- ask patient questions
What can we do about sleep bruxism?
- stablisation
- splint
- CBT
- Physiotherapy
- warm compress
- soft bite guard
- ibuprofen
- NTI device
- Anterior repositioning splint
- Arthrocentesis
What are the 3 main splints to consider?
- stabilisation splint
- B splint
- Anterior repositioning splint
What are some more mild splints?
- soft splint
- local occlusal interference splint
What does a stabalisation splint do?
help patients with masticatory muscle pain by reducing:
-pain intensity
-muscle tenderness
and allowing mouth opening to increase
What are some key features of a stabilisation splint?
- made in centric relation (when muscles doing least amount of work
- created in ideal occlusion
- made from hard acrylic (less likely to be chewed)
What is needed to make a stabilisation splint?
- Alginate impression
- Centric relation jaw registration
- Facebow record
What is a B-splint?
A smaller splint with localised pressure covering the anterior 6 teeth
What splint covers only the anterior 6 teeth?
A B-splint
What is an anterior repositioning splint?
A splint which creates more space in the joint capsule therefore allowing the disc to move and gradually moves back into place due to elastic fibres
In what TMD is an anterior repositioning splint used?
Disc displacement WITH reduction
How long does an anterior repositioning splint need to be worn for?
24/7 for 3 months
What does CBT stand for?
Cognitive Behaviour Therapy
What is CBT?
It is a way of talking about:
- how you think about yourself, the world and other people
- how what you do affects your thoughts
How can CBT help
Helps “how you think” (COGNITIVE) and “what you do (BEHAVIOUR) and helps you focus on the here and now problems to improve your current state of mind
What is Arthocentesis?
A clinical procedure of removing arthritic waste products from joint capsule to help disc move more smoothly (removing synovial fluid from synovial joint)
What patients is arthrocentesis used on?
Patients with disc displacement WITHOUT reduction
What treatment is given to patients with disc displacement with reduction?
Anterior repositioning splint
What treatment is given to patients with disc displacement without reduction?
Arthrocentesis
