Anatomy of TMJ and intro to Occlusion Flashcards
Four anatomic determinants of occlusion
Left TMJ
Right TMJ
Permanent Dentition
The neuromuscular system
Articular Eminence/ Inclination (slope) varies with
Age Gender Patients Parafunctional Habits Local Pathology Systemic Pathology
what is the articular eminence
anterior wall of the TMJ
- normal is 30 degrees
Mandibular elevators
AKA closers Masseter Temporalis Lateral pterygoid medial pterygoid
Temporalis
Attachments
Action
Origin - temporal fossa and temporal fascia
Inserts - coronoid process and anterior border of ramus
Functions- elevates jaw and retracts and positions mandible clenches teeth
Masseter
Attachments
Action
Origin: Superficial portion - anterior 2/3 of lower border of zygomatic arch
Deep portion - medial surface of zygomatic arch
Function : elevates jaw and clenches teeth
lateral pterygoid
Attachments
Action
Origin of Superior head - infratemporal surface of sphenoid of greater wing
Inferior head - lateral surface od lateral pterygoid plate
Insert: Anterior portion of condylar neck and TMJ capsule
Function - protrusion of mandible pulls articular disc forawrd and assists in rotary movements of mandible
medial pterygoid
Origin- medial surface of lateral pterygoid plate, pryamidal process of palatine bone, maxillary tuberosity
Inserts - posterior and lower part of the medial surface of ramus and angle of mandible
Functions- protracts and elevates mandible - assists rotary movements lateral of mandible
rotation takes place where
in the INFERIOR ARTICULAR SPACE
translation occurs where?
in the superior articular space
as move forward and down
direction of translation
antero inferior
forward and down
occuring in the superior articular space
articular eminence
mandible is sliding on
slope
anterior wall of TMJ
anterior wall of TMJ
articular eminence
downward and inferior
slope of articular eminence in infant
pretty flat - or shallow
same with when you get older
function of temporalis
mandible to close
‘elevator’
