surveying

Free Powerpoint Templates
SURVEYING IN
REMOVABLE PARTIAL
DENTURES
Dr Farah Ahmed
1

SURVEY
2
• To examine as to condition,value or situation , to
appraise.
• To determine the form and position of a given
entity by taking linear and angular
measurements

SURVEYING
3
An analysis and comparison of the prominence
of intraoral contours associated with the
fabrication of a dental prosthesis.

SURVEYOR
4
A surveyor is essentially a parallelometer, an
instrument used to determine the relative
parallelism of surfaces of teeth or other areas on
a cast of the jaws.
(Stewart)

A paralleling instrument used in the construction
of a dental prosthesis to locate and delineate the
contours and relative positions of abutment teeth
and associated structures.
-(GPT-8)
5

“Intelligent use of a dental surveyor is the best
way to prevent the occurrence of countless
problems frequently related to oral rehabilitation
with RPDs”
-Dr O C Applegate
6

The History and Development of the Dental
7
(Robert L Engelmier)-JOP vol 11(march)
Surveyor
2002
“Reduced to its simplest terms , surveying a tooth
is a mechanical method of obtaining its height of
contour accurately. If a vertical plane is brought
into contact with a curved surface it will touch at
the greatest bulge on the convexity and nowhere
else.”
–Dr A H Schmidt (1953)

Manual Surveying
• Visual survey
• Eyeballing
• Dr W M Randall’s
technique for
surveying.(1890)
8

Early Paralleling instruments
THE CHAYES
9
PARALLELOMETER (circa 1920)

THE CHAYES PARALLELOMETER
SYSTEM
10

11
Paralleling device used as a jig for the Grisworld Attachment System

The First Dental Surveyor
12
• Dr Rudolph Hanau (1917)
• Dr A J Fortunati (1918)
• Dr Edward Kennedy
• The Philadelphia Dental Clinic club
• Noble G Wills
• Weinstein and Roth(1923)

THE ROBINSON SURVEYOR (circa
1918)
13

14
DENTAL SURVEYING APPARATUS – HANAU
(1917)

The Basic Dental Surveyor
1. Level platform
2. Cast holder
3. Vertical arm
4. Horizontal arm
5. Surveying arm
6. Interchangeable
Surveying tools
15

Scientific Exhibits American Dental
Association (1948)
16
1. Ney (1923)
2. Brown Maier (1925)
3. Wills (1929)
4. Lentz –Circa (1935)
5.Lineer (1937)
6. Ney (1937)

7. Franzwa (1937)
8.Ringle-Hiatt-Smith (1944) 9.
McKay (1944)
10. Hagman (1944)
11. Roach (1944)
17

A. Original Ney’s Surveyor (1923)
B. Current model of Ney’s Surveyor (1937)
C. Modified Ney’s Surveyor (mid 1960s)
18

Will’s Surveyor 1937
19
Recent Design Of The Will’ Surveyor

The Roach Surveyor (1944)
20

RECENT INNOVATIONS
21

Austenal 42 inch
blockout
surveyor
22
Austenal Micro
Analyser

PARTS OF A SURVEYOR
British dental journal, volume 189, no. 10, november 25 ,2000
1. Level platform
2. Vertical arm
3. Horizontal arm
4. Surveying arm
5. Cast holder
6. Accessory tools
23

Accessories/surveying tools
1.Analyzing rod
2.Carbon(graphite) marker
3.Undercut gauges
24
4. Wax knife
5.Milling devices (with handpiece holder)

Analysing Rod
25

Identifies undercut areas and to determine the
parallelism of surfaces without marking the cast.
26

Graphite Marker
27

• moved around the tooth and along the alveolar
ridge
• the tip of the marker should be level with the
gingival margin.
28

False Survey Line
29

Undercut Gauges
30

the shank and head should contact the cast
simultaneously.
• more sophisticated, types of undercut gauge are
available such as dial gauges and electronic
gauges.
31

Wax Knife
32

• To blockout
undesirable undercuts
• To prepare guiding
planes
33

1. Survey line
2. Undercut
3. Guiding planes
4. Path of insertion
5. Path of displacement
35

SURVEY LINE
36
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.
-GPT 8

TYPES OF SURVEY LINES
37
• Blatterfein classified survey lines as:
1. High survey Line
2. Medium Survey Line
3. Low Survey line
4. Diagonal Survey Line

•Found
surface
parallel
margin
near the occlusal
often
of a tooth
to the gingival
•It results from abnormal
inclination of the teeth
surfaces of the
•lingual
lower teeth and buccal
surfaces of the upper teeth.
•Wrought wire clasp used
High Survey Line
38
38

•It is situated across
the center of the tooth
•Exhibits a slight
occlusogingival incline
from the near zone to
the far zone.
•Aker’s or Roach clasp
Medium Survey Line
38
39

•It is situated close to and
parallel to the gingival
margin.
•It frequently occurs as a
result of marked
inclination of the tooth and
may also occur on
conically shaped tooth.
•Modified T clasp
Low Survey Line
38
40

It travels diagonally
from near the occlusal
surface in the near
zone to the gingiva in
the far zone.
Reverse circlet clasp
Diagonal Survey Line
38
41

Class I:
•Survey line runs diagonally
across the tooth surface.
•The type of clasp indicated
is occlusally approaching
cast clasp with terminal third
engaging the undercut.
Ney’s Classification
38
42

Class II: Survey line also
runs diagonally across
the tooth surface but as a
mirror image of Class I
line. Here a gingivally
approaching clasp
. arm is suggested.
43
43

Class III:
Survey line is parallel
to the occlusal
surface and lies just
below it
44

Undercut
the portion of the surface of an object that is
below the height of contour in relationship to
the path of placement
-(GPT 8)
45

Types Of Undercuts
Tooth Undercuts (Proximal
undercuts)
Soft Tissues or bony
Undercuts(on lingual side
of ridge)
46
46

• 0.25 mm - 0.01”
• 0.5 mm – 0.02”
• 0.75 mm – 0.03”
47
chrome cobalt
cast gold
stainless steel

Guiding Planes
48
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.

Two or more parallel axial surfaces on abutment teeth which can
be used to limit the path of insertion and improve the stability of a
removable prosthesis. Guide surfaces may occur naturally on
teeth but more commonly need to be prepared.
49

PATH OF INSERTION
50
Surveying removable partial dentures:the importance of guiding planes
and path of insertion and stability –O L Bezzon et al (JPD October 1997
vol 78 no.4 )
the specific direction in which a prosthesis is
placed on the abutment teeth or dental
implant(s)
• path of withdrawal (reverse of path of insertion)
• path of placement

The RPD path of insertion and withdrawal is the
direction in which the prosthesis moves in
relation to the support system when it is seated
in or removed from the mouth, guided by the
contact of its rigid parts with the abutments.
(GPT-8)
51

A single path of insertion
52
52

Multiple Paths of Insertion
53

Two paths of insertion
54
Rotational path of insertion

Potential Path of Dislodgement
Regardless of the path of insertion the path of
dislodgement results from masticatory function that pulls
the prosthesis in a direction perpendicular to the occlusal
plane.
55

USES OF A SURVEYOR
56
1. Surveying the diagnostic cast
2. Tripoding the cast
3. Transferring tripod marks to another cast
4. Contouring wax patterns

5. Contouring cast restorations
6. Placing internal attachments and rests
7. Surveying the master cast
57

Process Of Surveying
58
1. Preliminary visual assessment of the study
cast.
2. Initial survey.
3. Analysis.
4. Final survey

Visual assesment:
59
• Eyeballing
• Form and arrangement of teeth
• Potential problem areas

Anterior tilt (‘heels up’)
60
Posterior tilt (‘heels down’).

Left and Right Tilts
61

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 gauges
62

Analysis
63
• Occlusal plane horizontal
• Consider:
1. Appearance.
2. Interference.
3. Retention

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.
64

posterior tilt so that the analysing
rod is parallel with the mesiolabial
surfaces of abutment teeth.
65
contact of abutment tooth over the
whole of the mesiolabial surface
and a much better appearance
results.

Interferences:
66

Interferences in the maxillary arch
Maxillary tori
67

Exostoses and undercuts on maxillary buccal surfaces
68

Interferences in the mandibular arch
Mandibular tori
69

Lingually tilted premolars
70

Undercuts adjacent to pear
shaped pads
71
Bony prominences on facial surface
of mand canines

Retention:
72

Final Survey
• The aims for optimum
retention should be to
provide:
• Resistance along the
path of displacement.
• Resistance along the
path of withdrawal
73

•guide surfaces are used to provide resistance to displacement
•retentive portion of the clasp needs only to resist movement along the path of
withdrawal
• positioned solely with reference to the red survey line.
74

75
Gingivally approaching clasp
positioned at the cross-over point
of the survey lines.
•survey lines converge mesially or
distally
•the tip of an occlusally approaching
clasp can engage the common area of
undercut.

Tripoding the cast
76

Alternate method of tripoding
77

Other Methods of Tripoding
78
• Pin cemented in the centre of the cast
• Use of protractor fixed on surveyor
• Use of dental bur in place of pin
• Use of position recorder device on a surveyor
• Use of plastic plate and impression of cusp tip
• Device with adjustable arms
• Use of plastic tray and impression
• Smooth or threaded pin with sleeve
• Use of inclinometer
• Key and keyway system
• Tripoder attachment

Transferring tripod marks to
another cast
• 3 anatomical points
marked on diagnostic
cast
• Same points marked
on 2nd cast with
analysing rod
79

Contouring the wax patterns
• With cast on
surveying table , tilt
adjusted to original
tilt.
• Guiding planes
• Height of contour
80

Contouring Crowns & cast
restorations
81
• Shape of wax pattern altered during
casting & finishing.
• Working cast with restorations placed at
original tilt
• Cylinder stone.
• Guide planes refined.

Placing internal attachments/rests
• Intracoronal retainers.
• Surveyor acts as a drill press
82

OBJECTIVES OF SURVEYING
83
1. Path Of insertion
2. Guiding planes
3. Height of contour
4. Dental and osseous contours
5. Soft tissue contours

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
84

Maintenance of Surveyor
85
• Wipe the base of surveying table and surveying
platform with alcohol or acetone soaked gauge
pad.
• Acrylic resin powder can be sprayed for smooth
gliding.
• Machine oil should be applied to vertical arm
before and after use, each time.

SUMMARY
86
Surveying is undertaken to obtain information
that will help us decide:
(1) The optimum path of insertion of the denture
which in turn is influenced by:
• the need to use guiding surfaces to achieve a
pleasing appearance.

• the need to avoid interference by the teeth or
ridges with correct positioning of denture
components.
• the need to use guide surfaces for retention.
(2) The design, material and position of clasps.
87

MICROSURVEYOR
89

1. O. L. Bezzon, M. G. C. Mattos, R. F. Ribero,
Surveying removable partial dentures: the importance of guiding
planes and path of insertion for stability.
J Prosthet Dent 1997;78:412-18.
2. J. C. Davenport, R. M. Basker, J. R. Heath, J. P. Ralph, and P-O.
Glantz
Surveying.
British Dental Journal 2000, vol.189(10):532-42
3. Robert L. Engelmeier
The History and Development of the Dental Surveyor: Part I
Journal of Prosthodontics, Vol 11 No 1, 2002: pp 11-18.
92

The History and Development of the Dental Surveyor: Part II
Journal of Prosthodontics,VOL11,No 2, 2002: pp122-30.
The History and Development of the Dental Surveyor: Part III
Journal of Prosthodontics,VOL13,No 3,2004: pp 195-202
6. Stewart’s Clinical Removable Partial Prosthodontics,3rd Edition,
Survey and design
7. McCracken’s Removable Partial Prosthodontics,11th Ed
93

surveying

Recommended

Recommended

More Related Content

Similar to surveying

Similar to surveying (20)

More from SiddharthSingh639

More from SiddharthSingh639 (16)

Recently uploaded

Recently uploaded (20)

surveying