tempromandibular joint and movements mandibular [ t m j ]
DESCRIPTION
TEMPROMANDIBULAR JOINT AND MOVEMENTS MANDIBULAR [ T M J ]. Is the articulation between the mandible and the cranium . It is a bilateral articulation. Anatomy. Articular fossa and eminence . Condylar head . Articular disc (meniscus). Articular capsule (capsular ligament) . - PowerPoint PPT PresentationTRANSCRIPT
TEMPROMANDIBULAR JOINT ANDMOVEMENTS MANDIBULAR
[T M J]
1. Is the articulation between the mandible and the cranium .
2. It is a bilateral articulation .
AnatomyAnatomy1. Articular fossa and
eminence .
2. Condylar head .
3. Articular disc (meniscus).
4. Articular capsule (capsular ligament) .
5. TMJ ligament .
6. Synovial membrane .
THE BASIC MOVEMENTS OF THE MANDIELE
1. Rotation Movement
= hinge movement .
1. Translation Movement
(gliding movement.)
Hinge movement = rotationHinge movement = rotation Rotation movement =
hinge movement.
It is the rotation of the
mandible around an
imaginary hinge axis at
the centers of the
condyles. It occurs in the lower
compartment of the joint
Gliding or translationGliding or translation
It is the body movement of the mandible.It occurs in the upper compartment.
Condyle in retroded .no movement position
Condyle performing rotation=hinge movement Condyle
performing anterior translation=gliding.
intercusbal intercusbal position from position from which hinge which hinge movement will movement will startstart
No TranslationNo Translation
Sagittal view=lateral view
Protrosion movementProtrosion movement
It is the forward movement of the mandible.
The mandible does not move in pure forward movement.
The mandible moves down ward and forward = Gliding = translation movement.
It occurs when the mandible moves from retroded position to -edge to edge position- to- reverse over jet, of anterior teeth.
Excursive MovementsExcursive Movements
Protrusive – No Posterior Contact
The lower anterior teeth ride up the lingual of the maxillary anterior teeth as the jaw goes forward.
Condylar path inclination varies according to the amount of protrusion. a-b Sagittal condylar path inclination. Centric relation position of the condyle. 4-P. 4 mm protrusion.8P. 8 mm protrusion
MP
MO
ICPRCP
HA
MP = Maximal protrusion
ICP = Intercuspal position
RCP= Retruded Contact position
HA = Hinge axis
MO = Maximum opening
EE=edge to edge
Posselt’s Figure
Habitual Arc of ClosureHabitual Arc of Closure
Christensen Phenomena When the mandible moves to edge to edge position , separation occurs distally between the natural dentition or occlusion rims .
Protrusive
Record
The protrusive relationship determines the angle of the horizontal condylar path
Lateral Movement .Working side = the side which the movement take place
Lateral Movement. ) non working side =the side which the
mandible moves away from.
Lateral movement of the mandible
The Condylar Path
1. Horizontal Condylar Path .
2. Lateral Condylar Path .
3. The Condylar Path Angle .
Vertical Dimension of rest
The vertical dimension of the face when the mandible is in rest position.
Vertical Dimension of occlusion
The vertical dimension of the face when the teeth are in contact in centric occlusion.
The centric relationThe centric relation
It is the relation between the mandible and the maxilla when the mandible in the physiologic retroded position at the vertical dimension of occlusion.
Importance: it is the point from which all movemnt of the mandible will start and end must be recorded to arrange the teeth in this position