Dental articulator

1. DENTAL
ARTICULATOR
Pithiwat UASUWAN, D.D.S.
Master of Science (Prosthodontics)
Faculty of Dentistry, Khon Kaen University

2. CONTENT
➤ Evaluation of articulator and occlusal concept
➤ Articulator type
➤ Mandibular closure and opening in CR
➤ Facebow transfer
➤ Mounting cast in CR
➤ Mounting in MIP
➤ Condylar guidance
➤ Bennett angle
➤ Setting of condylar guidance
➤ Condylar guidance duplication
➤ Clinical consideration
➤ Border of movement 2

3. EVOLUTION OF ARTICULATOR AND OCCLUSAL CONCEPT
3

4. ARTICULATOR TYPE
➤ Fully-adjustable
➤ Plane line,
non adjustable
➤ Semi-adjustable
“mechanical analogues” of mandibular closure and movements
4

5. ARTICULATOR TYPE
terminal path of closure
excursive movement
Simple occluders and plane line articulators
5

6. Dentatus Hanau H2 Whipmix
Non arcon Arcon
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ARTICULATOR TYPE

7. Arcon Non Arcon
ARTICULATOR TYPE
The angle between the condylar track and maxillary plane
Clinically irrelevant
7

8. MIP
CO
Closing trajectory
MANDIBULAR CLOSURE AND OPENING IN CR
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9. MANDIBULAR CLOSURE AND OPENING IN CR
Purely rotational movement
20 mm
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10. MANDIBULAR CLOSURE AND OPENING IN CR
Center of rotation and arcs of closure
inaccurate interocclusal contact
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11. Vertical axis of rotation discrepancies
MANDIBULAR CLOSURE AND OPENING IN CR
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12. ➤ Arbitrary hinge axis and earpiece locator
FACEBOW TRANSFER
Earpiece facebow“Snow facebow” skin facebow
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13. FACEBOW TRANSFER
Kinematic facebow
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14. FACEBOW TRANSFER
True vs arbitrary hinge axis
5 mm
8 mm
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15. ➤ Symmetrical relation of the facebow
FACEBOW TRANSFER
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16. ➤ Relation of maxillary cast to horizontal reference planes
FACEBOW TRANSFER
“Interpupillary line”
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17. FACEBOW TRANSFER
Non parallelism between interpupillary line and intercondylar axis
The relation to the intercondylar axis is more
mount the upper cast parallel to the upper member of
articulator
Esthetic orientation is more important!
mount the cast with esthetics occlusal
plane arbitrarily related to the horizon
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18. ➤ Third reference point and plane
FACEBOW TRANSFER
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19. ➤ Is the facebow necessary at all?
FACEBOW TRANSFER
- no evidence of better
clinical result of using
- high long term success
Changing the VD on a
misaligned horizontal axis
Error in closing arc and
cuspal discrepancies
In Scandinavia
- Mean value setting
- The upper cast mounts with
occlusal plane parallel to the
upper member
19

20. ➤ Interocclusal records
Bimanual Chin point
MOUNTING CAST IN CR
Median variability
- Swallowing or free-closure records is 0.4 mm
- Chin point guidance is 0.14 mm
- Chin point with ant jig is 0.07 mm
- Bilateral manipulation is 0.05 mm 20

21. ➤ Gothic arch registration
MOUNTING CAST IN CR
https://www.youtube.com/watch?v=xy1f00QB9EE
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22. ➤Gothic arch
➤Tin foil wafer with Zn oxide, and eugenol and
compound
➤Light cure acrylic wafer
➤Anterior frontal jig in compound
➤Unrefined wax registration (pink wax)
➤Refined wax registration (pink wax plus Zn
oxide eugenol and aluwax)
MOUNTING CAST IN CR
Effect of recording material on mounting CR
22

23. Unrefined wax wafer
Light cure
Acrylic wafer
CBP, frontal jig,
tin foil,
refined wax wafer
>>
Effect of recording material on mounting CR
MOUNTING CAST IN CR
Vertical accuracy
23

24. Discrepancy : PVS and self cure acrylic less than 0.05 mm
Vertical accuracy
Polyether Wax Compound Acrylic resin> >>
Effect of recording material on mounting CR
MOUNTING CAST IN CR
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25. Influence of different material
is smaller than
clinical reproducibility of the method
MOUNTING CAST IN CR
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26. MOUNTING IN MIP
The best is
“no” media
Metal master cast
- PVS 101 micron
- Polyether 107 micron
- Wax 168 micron
Epoxy cast
- 0.5 mm for all materials
Clinical indifference
1
2 If media is used
Vertical discrepancy
26

27. “mean angle made by the protrusive path of movement
relative to the horizontal for a particular degree of protrusion”
CONDYLAR GUIDANCE
Condylar guidance angle
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28. Non working WorkingProtrusion
Protrusive
interocclusal record
Lateral
interocclusal record
Pantographic tracing or
dynamic registration
CONDYLAR GUIDANCE
➤ Protrusive and non working condylar guidance
28

29. Fischer angle : 6 degrees
Protrusion
Non working
Non working
Protrusion
CONDYLAR GUIDANCE
➤ Protrusive and non working condylar guidance
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30. BENNETT ANGLE (MEDIOTRUSIVE ANGLE)
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31. SETTING OF CONDYLAR GUIDANCE
Custom mold Curved guide
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32. ➤ Usually 30-40 degrees
➤ Vary from 21-64 degrees
➤ Class I 58 degrees
➤ Class II 61 degrees
➤ Class III 47 degrees
Skeletal relationship
SETTING OF CONDYLAR GUIDANCE
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33. Denar Cadiax Compact : electronics
high degree of repeatability
https://www.youtube.com/watch?v=CTwvI9B6Ksk 33
SETTING OF CONDYLAR GUIDANCE
Pantographic tracing

34. CONDYLAR GUIDANCE DUPLICATION
Direct adjustment from condylar setting
Custom anterior guidance
1
2
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35. Condylar determinants on tooth morphology
CLINICAL CONSIDERATION
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36. Compensating curveOcclusal plane
Condylar guidance
Anterior guidance
Cuspal angulation and height
Degree of vertical separation
CLINICAL CONSIDERATION
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37. BORDER OF MOVEMENT
Ability to reach the border limits of movement
Neuromuscular health
? 37

38. BORDER OF MOVEMENT
Muscle co-contraction
“Protective reflex”
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39. “The measure of intelligence
is the ability to change”
79
- Albert Einstein“The measure of intelligence is the
ability to change”
THANK YOU
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