Tmj Dysfunction Flashcards
Definition TMJ
Disorder of the muscles of mastication, temporomandibular joints and associated structures
Tmj function?
In charge of rotation + gliding
3 Components for TMJ to occur
●Predisposition
●Tissue alteration
●Stress
Predisposition
●Intrinsic: genetic development of mms ligs and or bones
●Extrinsic: trauma to neck face or jaw
Tissue alteration
Can occur to skeletal, dental or neuromuscular structures
Malocclusion
Teeth not aligned properly
Stress
Increased tone of mms of mastication due to jaw clenching, bruxism (tooth grinding during sleep)
Lock jaw
Opening lock- condyle is anterior to disc and is unable to return posteriorly- jaw cannot close
Close lock- Disc is displaced anteriorly + condyle cannot move past posterior portion of Disc- will not open more than 10 millimeters
Reciprocal clicking
Happens on both opening and closing of jaw
Temporalis
●Elevates jaw
●Paplate- ask clt to clench jaw
Masseter
●Superficial + deep layer
●Elevates mandible- deep layer also retracts
●Paplate- clench jaw
Medial pterygoid
●Both together elevate mandible
●Unilaterally moves mandible to opposing side
●Deeper to masseter
Lateral pterygoid
●Superior- pulls Disc ant when mandible opens
●Inferior- depresses jaw + moves jaw to opposite side unilaterally
●Palpate- resisting mandibular depression
Digastric
●2 bellies
●Post attach to mastoid
●Ant attach to inside of mandible
●Depresses + unilaterally side to side
●Palpate- resisting depression
Mylohyoid
●Forms the floor of the mouth (a suprahyoid)
●Depresses mandible + tightens floor of mouth
