Opening
Opening
Opening
Opening
Posselt’s
Figure
Posselt’s Investigations
Posselt’s Investigations
Posselt’s Figure
Posselt’s Figure
MP
ICP
RCP
HA
MP = Maximal protrusion
ICP = Intercuspal position
RCP= Retruded Contact position
HA = Hinge axis
MO = Maximum opening
MO
Posselt’s Figure – top edge
MP
ICP
IG
RCP
EE
Definitions
Articulators
– A mechanical representation of the jaws and
temporo-mandibular joints
Use of articulators
Diagnosis
• slides and occlusal relationships
Treatment planning
• Diagnostic wax - up
• Occlusal adjustment
Fabrication of Splint / Prostheses
Articulators
Types
– Simple Hinge
– Average Value
– Semi-adjustable
– Fully adjustable
Articulators
Cast Holder
Cast Holder
Average Value
Articulators
BONWILL 1854
4”
4”
Articulators
Average Value
4”
4”
Articulators
Average Value
Articulators
Denar II - Arcon
Dentatus
Non Arcon
Denar II
Adjustable Condylar Angle, ISS & PSS
Articulators
Semi-adjustable
Can alter;
•TMJ to Incisor distance
•Bennett Angle
•Condylor Guidance
Angle
•Incisal guidance plate
Articulators
•Needs Facebow
recording
•Ideally should be used
for complete denture
cases
Facebow recording
For semi adjustable articulator
Fully adustable: Denar 5
Posterior wall
Superior wall
Medial wall
Inclination of superior wall
Condylar angle
Intercondylar (& glenoid fossa) distance
ISS
Denar 5a
Pantographic recording
For fully adjustable articulator
lots
Difficulty
of
use
none
Hand Av
Held Value
S-A
Fully
Adjustable
lots
Amount of adjustment
none
Hand Av
Held Value
S-A
Fully
Adjustable
lots
Cost
none
Hand Av
Held Value
S-A
Fully
Adjustable
Articulator use vs time vs cost
lots
lots
Amount of adjustment
Difficulty
of
use
Cost
none
none
Hand Av
Held Value
S-A
Fully
Adjustable
What if patient doesn’t match
articulator?
Articulator
Patient
Articulators
Articulators
Therefore the distance from the condyle to the teeth is crucial
We obtain a measurement of this distance with a facebow
Facebow
Interocclusal record
Used to locate the lower model to the upper
If lots of good stable occlusal contacts then no IOR
needed
If need an RCP record, then we need an IOR that is thick
and strong enough to obtain a record with the teeth
separated and in terminal hinge axis e.g. Moyco Extra
Hard Beauty wax
For routine ICP records when carrying out multiple crowns
/ bridgework, Blu-mousse just over the tooth preps is
usually sufficient
Aids to obtaining THA
Bimanual manipulation
Cotton wool rolls
Anterior “jig”
Splint therapy
Chin-point guidance
Anterior jig
Cold-cure acrylic (Duralay/Trim)
Greenstick
Anterior jig (trimmed)
Provides inclined plane
Separation of posterior teeth
Allows the use of easy flowing
occlusal recording media
such as Blu-Mousse
Anterior Jig
From Howatt, Capp & Barrett
Clinically useful settings for
articulator
Condylar angle 25°
Immediate side shift 0.3mm
Progressive side shift 6°
Incisal guidance table
Allows shape of palatal to be reproduced
Allows length of incisors to be maintained
Tooth to be prepped
Shape created is
the inverse of Posselt’s figure
Following tooth prep
Tooth form reconstructed
Summary
The choice of articulator depends upon
such factors as;
– Intended use
– Availability of equipment
– Patient's occlusion
- Skill of the technician
- Expense
- Skill of the operator
– The more closely the articulator matches the
patients anatomy, usually the better the
outcome and the less adjustment is required
at chairside on fitting prostheses.