Surveying in removable partial denture..

Surveying in removable partial denture

1. SURVEYING IN REMOVABLE
PARTIAL DENTURES
Ahmed Ashraf Awad
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2. SURVEYOR:
dental surveyor has been defined as an
instrument used to determine the relative
parallelism of two or more surfaces of the
teeth or other parts of the cast of a dental
arch.
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3. OBJECTIVES OF SURVEYING
1.Path Of insertion
2.Guiding planes
3.Height of contour
4.Dental and osseous contours
5.Soft tissue contours
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4. 6-Cast position and relation to path of insertion
7. Transfer of design to master cast
8. Blockout
9. Develop axial contours
10. Machine guiding planes
11. Intracoronal retainers
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5. Two widely used surveyors
➢Ney
➢Jelenko
Jelenko arm swivel while Ney is fixed
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7. THE BASIC DENTAL
SURVEYOR
1.Level platform
2.Cast holder
3.Vertical arm
4.Horizontal arm
5.Surveying arm
6.Interchangeable Surveying tools
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8. Accessories/surveying tools
1.Analyzing rod
2.Carbon(graphite) marker
3.Undercut gauges
4. Wax knife(trimmer)
5.Milling devices (with headpiece holder)
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9. ANALYZING ROD
Identifies undercut areas and to determine the
parallelism of surfaces without marking the cast
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10. .Carbon marker
moved around the tooth and along the alveolar ridge
the tip of the marker should be level with the gingival margin.
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11. UNDERCUT GAUGES
the shank and head should contact the cast simultaneously
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12. WAX KNIFE (TRIMMER)
➢To blockout undesirable undercuts
➢To prepare guiding planes
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13. PURPOSE OF SURVEYOR
1.surveying the diagnostic cast
2.recontouring abutment teeth on the diagnostic cast
3.Contouring wax patterns
4.measuring a specific depth of underCut
5.surveying ceramic veneer crowns
6.Placing intracranial retainers
7.Placing internal rests
8.Machining cast restorations
9.Blockout master cast
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14. SURVEY LINE
Survey line is a line drawn on a tooth/
teeth of a cast by means of a surveyor for
the purpose of determining the various
parts a clasp/clasps .
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15. TYPES OF SURVEY LINES
Blatterfein classified survey lines as:
1.High survey Line
2.Medium Survey Line
3.Low Survey line
4.Diagonal Survey Line
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16. HIGH SURVEY LINE
Found near the occlusal surface of a tooth often
parallel to the gingival margin
Wrought wire clasp used
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17. MEDIUM SURVEY LINE
It is situated across the center of the tooth
Aker’s or Roach clasp
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18. LOW SURVEY LINE
It is situated close to and parallel to the
gingival margin
Modified T clasp
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19. DIAGONAL SURVEY LINE
It travels diagonally from the near the occlusal
surface in the near zone to the gingiva in the far
zone
Reverse action clasp
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20. UNDERCUT
the portion of the surface of an object that is below the height of
contour in relationship to the path of placement

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21. TYPES OF UNDERCUTS
Tooth Undercuts
(Proximal undercuts)
Soft Tissues or bony Undercuts
(on lingual side of ridge)
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22. TOOTH UNDERCUT
Desirable undercuts depth
0.01” chrome cobalt
0.02” cast gold
0.03” stainless steel wrought wire
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23. GUIDING PLANES
vertically parallel surfaces on abutment teeth or/and dental
implant abutments oriented so as to contribute to the direction of
the path of placement and removal of a removable dental
prosthesis
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24. PATH OF INSERTION
the specific direction in which a prosthesis is placed
on the abutment teeth or dental implant(s)
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25. PROCESS OF SURVEYING
1.Preliminary visual assessment of the study
cast.
2. Initial survey.
3. Analysis.
4. Final survey
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26. VISUAL ASSESMENT
➢Eyeballing
➢Form and arrangement of teeth
➢Potential problem areas
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27. INITIAL SURVEY
-Cast positioned with the occlusal plane horizontal.
-The position of the survey lines.
-‘Triangle of light’ between the marker and the
cervical part of the tooth.
-Undercut gauge
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28. FACTORS THAT DETERMINE PATH
OF PLACEMENT AND REMOVAL
Occlusal plane horizontal
The factors that determine the path of placement and
removal are guiding planes, retentive areas, interference,
and esthetics. Additionally, if an implant is part of the
design its long axis is considered in relation to the path or
placement and removal.
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31. APPEARANCE:
Undercuts on the mesial aspects of the
abutment teeth.
Unsightly gap between the denture saddle
and the abutment teeth gingival to the contact
point.
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33. posterior tilt so that the analysing rod
is parallel with the mesiolabial
surfaces of abutment teeth.
contact of abutment tooth over the
whole of the mesiolabial surface
and a much better appearance results.
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34. INTERFERENCES:
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37. RETENTION
•guide surfaces are used to provide resistance to
displacement
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38. TRIPODING THE CAST
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39. Objective of tripoding the cast
➢Help to return working cast to the surveyor in the same
relation as the proposed path of insertion for shaping wax
pattern, trimming blockout on the master cast or locating
clasp arm.
➢For future reference
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40. 3 anatomical points marked on diagnostic cast
Same points marked on 2
nd cast with analysing rod
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41. CONTOURING THE WAX
PATTERNS
With cast on surveying table , tilt
adjusted to original tilt.
Guiding planes
Height of contour
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42. CONTOURING CROWNS &
CAST RESTORATIONS
Shape of wax pattern altered during casting
& finishing.
Working cast with restorations placed at
original tilt
Cylinder stone.
Guide planes refined.
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43. PLACING INTERNAL
ATTACHMENTS/RESTS
Intracoronal retainers.
Surveyor acts as a drill press
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44. * Alan B. Carr and David T. Brown; McCracken’s
removable partial denture 13th edition 2016,
chapter 11.
* Rodney and Charles; Stewart’s clinical
removable partial denture 4th edition, chapter 7.
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