TMJ Surgery Flashcards
Which diseases can occur in the TMJ?
TMJ dysfunction
Jaw dislocation
Osteo-arthritis
Rheumatoid arthritis
Chondromatosis
Foreign body granuloma
Infection
Traumatic damage
Radiation damage
Ankylosis
Tumours
Which factors are involved in the aetiology of TMD?
Macrotrauma- one sudden incident of direct mechanical trauma
Microtrauma- repetitive overloading of TMJ (related to stress, clenching, bruxism)
Anatomy- class II jaw relation
Occlusal factors- deep bite, disharmony, lack of teeth
What are the symptoms of TMD?
Pain- muscular, capsular, intra-capsular (inside disc)
Reduced mobility- limited opening
Clicking/crepitus
Locking
What are the different parts of the articular disc?
Front- attached to lateral pterygoid (pulls on disc anteriorly)
Bilaminar zone (prevents disc from getting detached from TMJ)
-> collagen fibres
-> part is attached to posterior of condyle and part is attached to posterior of eminence (pulls back into place)
Disc is thin in the middle and can get perforated
What can happen to the bilaminar zone as a result of TMD?
Over time bilaminar zone collagen fibres lose elasticity and lose recoil ability following clenching (derangement of the joint)
How can the Lateral pterygoid be palpated?
Palpate behind tuberosity (lateral surface of lateral pterygoid plate)
-> if this is sore it suggests spasm of the muscle due to clenching, grinding, bruxism
What is meant by internal derangement of TMJ? What causes it?
Pathological mismatch between capacity of TMJ and excessive function
-> Excessive lateral loading on surface of the condyle- disc can become completely anteriorly dislocated (cannot be brought back by bilaminar zone)
What is meant by anterior dislocation of the TMJ with reduction? (initial)
Patient opens with a click (sore)- bilaminar zone is able to bring disc back
What is meant by anterior dislocation without reduction? (if untreated)
Bilaminar zone is unable to bring disc back (no/less pain but cannot open mouth widely)
What are the options for conservative management of TMD?
Counselling- stress causing grinding
Pain management - painkillers, anti-inflammatory like ibuprofen (treat cause not symptoms)
Joint rest- avoiding chewing hard foods (but chew on both sides), limit mouth opening (support chin with hand)
Physio- relax spasming muscles through stretching, using heat
Restoring occlusal stability- if high tooth or filling
Bite appliance
What are the functions of bite raising appliances when treating TMJ)
Eliminates occlusal interference
Works as habit breaker against grinding
Opens mouth slightly (prevents condyle moving up and back at area of bilaminar zone which is usually most inflamed
-> reduced loading on TMJ
What is the issue with treatment of anterior dislocation without reduction?
It will require surgery
Which special investigations can be used to aid your diagnosis of TMD
OPT
Arthrography/arthroscopy
MRI (magnetic resonance imaging)
How is arthrography of TMJ carried out? What can be seen?
Inject radiopaque material (lipidome) into TMJ and take image
-> Visualise superior and inferior compartments (split by disc)
-> You would see the meniscus of disc sitting in front of condyle (normally- would be at centre of condyle)
Why is MRI helpful in diagnosis of TMD?
Shows how lateral pterygoid is attached to the disc
-> You can see if it is dislocated
