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FRP - Crowns/Bridges/Wear/TMD/SDA/IMPLANTS > Occlusion > Flashcards

Flashcards in Occlusion Deck (30)
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definition of a stable occlusion

One in which occlusal contacts help to limit the possibility of tooth movement (drifting, tipping, over-eruption)


what is ICP
-describe this in terms of which teeth are contacting

The position of “best fit” between the maxillary and mandibular teeth (therefore, a position determined by the teeth)-The position which the mandible aims for at the end of the chewing cycle

-On posterior teeth, the lower buccal cusps and upper palatal cusps occlude against the fossae and marginal ridges of the opposing teeth
The lower incisal edges and canine tips occlude against the cingulum area of the opposing teeth


movement of working and non working sides

Working - Rotation

Non working - downward/forward/translation


name 3 forms of guidance and what teeth are involved

Anterior Guidance (Canines and Incisors)

Group Function (includes posterior teeth)

Balanced Articulation (complete dentures only)


describe anterior guidance

Anterior Guidance:
in excursions one or more anterior teeth contact and there is immediate “disclusion”of all the posterior teeth


describe group function

Group Function:
in excursions a number of teeth on the working side
contact and there is disclusion of teeth on the
non-working side


parafunction effect

Purposeless clenching and grinding of the teeth
Forces exerted are greater and of longer duration than during function
Contacts may occur in many positions of the mandible
Forces may be horizontally directed
Protective neuromuscular reflexes do not operate
Damage to the teeth, the periodontium, the muscles and joints may result


name some tooth positions

Retruded Contact Positon
• Intercuspal Positon
• Centric Occlusion
• Edge to Edge
• Protrusivecontact


name some jaw positions

Retruded Axis Posi:on
• Maximum Opening
• Centric Rela:on
• Protrusion
• Rest Posi:on


what is the rest position

Rela:onship of the mandible to the maxilla
when the patient is relaxed
and sitting upright
• Interocclusal clearance 2-3mm free way space


what is RCP

First tooth contact when the mandible is in
retruded axis positon
• Most superior anterior
positon of the condylar head in the glenoid fossa


what is a facebow and what does it record

Horizontal record of hinge axis of mandible
• A caliper-like instrument used to record the spacial relationship of the maxillary arch to some anatomic reference point or
• This relaConship is transferred to an articulator
• Facebow orients the maxillary cast in the same relationship
to the opening axis of the articulator
• Customarily the anatomic references are the mandibular
• condyles transverse horizontal axis and one other selected
anterior point


what measurement value for the reference plane locator

inferior orbital margin? - 43mm above lateral incisor


-how to mount an upper cast
-how to mount a lower cast

Upper cast - Facebow
Lower cast - registration


what to organise to:
Reorganised approach
Conform approach

Reorganised - RCP

Conform - ICP


when to use wax as a registration material

When there are enough teeth
and the bite in ICP is obvious
you don’t need wax.
• If too much wax is used and the
lower cast is mounted like this
the OVD will be increased and
the restoration will be high in the bite whenplaced.
• When using wax you must
ensure it is thin and cusp contact points
are visible


when to use registration paste

When ICP wont be
obvious to the technician
• Silicone paste that sets
• A small amount is needed
• Too thick and it will
increase the OVD
• Occlusal contacts must be
visible through the


acceptable articulator choices

semi adjustable
average value


what are the average values (of an average value articulator

• Sagittal Condylar Guidance Angle 30 degrees
• Bennet Angle 15 degrees
• Incisal Angle


What is the sagittal condylar guidance anlge
-what record is needed to set it

the angle at which the condyle descends down the glenoid fossaof the TMJ in the saggital plane
-protrusive record edge to edge


what is the bennett angle

angle decribed by orbiting angles during lateral protrusive movements
-distance the NW condyle moves medially measured in degrees compared to a straight path


what tooth/tooth contact occurs on the:
-NW side
-Working side

-NW - dissimilar cusps contact
-Working - similar cusps contact


what is centric occlusion

occlusion of opposing teeth, when mandible is in centric relation


what is centric relation

The maxillo-mandibular
relationship in which the
condyles articulate with the
thinnest avascular portion of
their respective disks with the
complex in the anteriorsuperior position against the
shapes of the articular eminencies.
• This position is independent of
tooth contact.
• It is restricted to a purely
rotary move- ment about the
transverse horizontal axis


what is the retruded contact position

• That guided occlusal
relationship occurring
at the most retruded
position of the condyles
in the joint cavities. A
position that may be
more retruded than the
centric relation position


what is the retruded axis position

The position the
mandibular condyle
adopts during the terminal hinge
movement of opening
or closing. See also
hinge axis.
• Anterior superior position of the condyle within the fossa


all dentures are made along what part of posselts

retruded arc of closure (Centric relation)


what aspects make up mutually protected occlusion

-canine guidance
-posterior disclusion in lateral excursion
-no NW/W side contact
-no protrusive interference


what are occlusal interferences

undesireable tooth contactsthat may produce mandibular deviationduring close to ICP/hinder smooth form to or from ICP


how to get patient into RCP

Bimanual manipulation of mandible into RAP
• Patient asked to slowly close together un first tooth contact (RCP)
• Bite registration taken in this position (RCP/CR record)
• Diagnostic wax up of normal anatomy of teeth in this position
• Vacuum form stent made on the wax up.
• Stent used as a template to try in planned changes with Protemp