Movements of the Mandible

Dr. Bistey, Tamásegyetemi adjunktus

Basic knowledge

Axis of the movements

Transversal

Vertical

Sagittal

Prominent points of the movements

Condyle

The centric point of the condyle

Symphysis, point „I”

Contact point of the lower central incisors

Condyle and symphysis points

The used planes

Frontal plane

Horisontal plane

Sagittal plane

Types of the movements

Free movements

Only the soft tissues and joint structure affect the movement and its pathway

Guided movements

The teeth or the prosthesis guide the mandible

Opening-closing

The movement during opening or closing the mouth

Free movement

Parts/phases

Pure hinge movements

Translation

Maximal opening

The transversal axis

Forward and backward movementPropulsion, repulsion

Guided movement

The tooth contact have important role in the pathway modality

Sagittal condyle pathway

Propulsion until incisal bite position

Relation of TMJ and molar teeth

Relation of molar teeth and incisors

Lateral movement

Vertical and sagittal axis

The mandible moves to one of the sides

Two sides:

Working side

Balance side

Tooth contact on working side

Non occlusion (gap) on balance side

The axis

Lateral movement and Bennett angle

Movement in the level of condyles

Christensen phenomena

Sagittal Christensen phenomena

Transversal Christensen phenomena

Edentulous patient

There is a gap at the place of molars/premolars between occlusal rims during propulsion movement

This can also be found in natural dentition

Lateral movement is resulted a gap formation on the balance side at the place of molars/premolars

This can also be found in natural dentition

The clinical importance

The artificial occlusal surface must be in harmony with the morphology of the TMJ and the sagittal pathway of the condyle. Otherwise the mandibular movements will reslt intable dentures during masticatory function.

Bennett movement

The bodily lateral movement or lateral shift of the mandible resulting from the movements of the condyles along the lateral inclines of the mandibular fossae during lateral jaw movement to the direction of the working side

Measured in: mm and ˚

1,5-2,0 mm or 10-15˚

Has several types according to the time order

Preliminary

Immediate side shift

Progressive divided

Symphysis point during movements

Border movements

Examination of the point „I” in three planes

Posselt envelope

Surface of the border movements

Occlusion and articulation of natural dentitionBite forms

Tooth contacts

Guiding surfaces

Guidance of teeth

Changing of occlusion in adults

Occlusal theories

Chewing

Thank you!