Articulators

OdontotechnologyOdontotechnology

Articulators

Well adjusted occlusal rims united & casts returned to lab casts

mounted on an articulator so that the teeth can be set up

Articulator•reproduces certain recorded relationship-position of the mandible in relation to the maxilla

•mechanical instrument designed to simulate the movements of the mandibular arch in relation to the maxillary arch

Articulator• reproduces certain recorded

relationship

• simulate certain movements

CJRCentric jaw relationship

ICP

The jaw relationship in which maximal occlusal contact occurs

The position of the mandibule when the relationship of opposing occlusial surfaces provides for maximum planned contact and intercuspation

Tooth-determined position.

Intercuspal Position ICP

Articulator• reproduces certain recorded

relationship

• simulate certain movements

Mandibular movements (basic)

• Excursions of the mandible in 3 directions– Downward movement-opening of

the mouth(20 mm incisor separation-retruded arc of closure)

– Forward movement-protrusive(20+ & anterior translation of the condyles down the slope of the articular eminence-condylar path)

– Lateral movements –sidewaysworking side-to witch the mandible moves-immediate shide shift &rotation about vertical axisnon working side-condyle moves down and medially, Bennett Angle

ADJUSTABILITY OF AN ARTICULATOR

The capability of the articulator to closely simulate the movements of the mandible (dependent on the adjustability of the

articulator elements)

ELEMENTS OF AN ARTICULATOR

• horizontal axis of rotation: variability of the position of the horizontal axis of rotation in relationship to the maxillary dental cast

• condylar inclination/fossa components:variability of the angle of the eminentia, directional guidance of the superior, posterior and medial walls of the fossa, and ability to simuate laterotrusive movement

ELEMENTS OF AN ARTICULATOR

• intercondylar distance: adjustability of the distance between the vertical axis of rotation

• Benett angle/Benett movement: adjustability of the angle and capability of stimuating sideshift movement

• incisal guidance: adjustability and ability to stimulate the anterior guidance of the natural dentition

NON ADJUSTABLE-SIMPLE HINGE

• opening and closing around a fixed axis (maximum intercuspation is the only position reproduced)

NON ADJUSTABLEClass II: Average value

• capable for lateral movement, some are cabaple of variable location of the horizontal axis of rotation

• all of this type have fixed, arbitrary condylar inclination settings, vertical axes of rotation settings, and Benett angle. No adjustment of these elements is available. Some have a provision for incisal guidance.

NON ADJUSTABLE-AVERAGE VALUE

• condylar angle relative to occlusal plane in average patient: : 34° Condylus sagittalis

• Capable for lateral movement, : 15° Condylus lateralis

• Incisal guidance:10°

No adjustment of movements

Casts mounted in an average position(average values)

Balkwill and Bonwill ▲s

ADJUSTABLE

• SEMI • Fully

ADJUSTABLEClass III: SEMI ADJUSTABLE

• simulate lateral, protrusive and Benett movements to varying degrees

• The amount of adjustability incorporated in the design provides the degree of simulation available.

SEMI ADJUSTABLE ARTICULATOR

• ARCON: condylar elements are on the lower member of the articulator, mechanical fossae are placed on the upper member of the articulator

• NON ARCON: condylar path simulating the glenoid fossae are attached to the lower member, condylar elements are placed on the uper portion of the articulator

FULLY ADJUSTABLE ARTICULATORS (IV.th year-gnathology)

ADJUSTABLECLASS IV: FULLY ADJUSTABLE

• accepts registration of all anatomic determinant of occlusal morphology, and most closely simulates the movement directed by these controls

• the incisal guidance can closely simulate the paths of natural dentition

• With facebow: The function of the facebow is to record the relationship of the maxillary arch to the horizontal axis of rotation of the mandible

• this class is fully utilized in extensive restorative procedures, as well as adjunct to diagnostic determinations of TMJ dysfunction.

FACEBOW instead of B & B ▲s