SURVERYING - Important to the ________ of appropriate mouth modifications (meaning tooth reduction but very minimal) for a removable partial denture | planning, execution, and verification |
SURVERYING - It is critical for planning the modifications of all tooth surfaces that will be involved with the ________ of the prosthesis | support, stabilization, and retention |
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 | dental surveyor |
widely used because of its simplicity and durability | Ney |
2 most widely used surveyors: | ney and jeleko |
Parts of Ney Surveyor | 1. Tool compartment/ Mandrel
2. Compartment lid
3. Vertical Arm
4. Horizontal arm
5. Survey table
6. Platform/Base
7. Rack for accessories
8. Paralleling tool or guideline marker
9. **collet and tightening knob-spindle |
Parts of the survey Table | 1. Tilt top (pinaglalagyan), model clamp-3, adjusting screw
2. Locking screw of tilt top
3. Ball pivot |
Tools in surveyor | 1. Metal sheath with carbon marker
2. Paralleling tool
3. Undercut gauges
4. Blades |
Difference of Ney from Jelenko | ✓ Has spring at the spindle knob
✓ Horizontal arm can be moved
✓ Smaller collet |
Purposes of surveyor | 1. Surveying the diagnostic cast
2. Contour wax patterns
3. Measuring specific depth of undercut
4. Surveying ceramic veneer crowns (FPD)
5. Placing intracoronal retainers |
Objectives of surveying: | 1. To determine the most desirable path of placement and removal
2. To identify the guiding planes
3. Locate retention areas (usable undercuts)
4. Determine tooth and bony interferences (soft tissue also have undercuts)
5. Delineate height of contour on abutment tooth
6. Record cast position in relation to selected path of placement |
types of undercut | usable and nonusable |
FACTORS THAT DETERMINE THE PATH OF INSERTION AND REMOVAL | guiding planes, retentive areas, esthetics, interference |
REST ➢ Primary purpose: | Provides vertical support |
REST; other purposes | 1. Maintains components in their planned positions
2. Maintains established occlusal relationships by preventing settling of denture
3. Prevents impingement of soft tissue
4. Direct and distributes occlusal loads to abutment teeth
5. Acts as an indirect retainer |
OCCLUSAL REST SEAT ➢ Outline from: | ROUNDED TRIANGULAR |
The base of the triangular shape (at the marginal ridge) should be at least ___ for both molars and premolars | 2.5 mm |
_____is lowered to provide bulk and to accommodate the origin of the occlusal rest with the least occlusal interference | Marginal ridge |
The angle formed by the occlusal rest and the vertical minor connector from which it originates should be ____ degrees | less than 90 |
TRUE OR FALSE: Rest seat preparation can be exaggerated for better support when it is prepared in cast restoration | TRUE |
Least desirable placement of a rest seat for esthetic reasons it can be used successfully to selected patients of the abutment is sounds and when a cast restoration is not indicated | INCISAL REST |
An incisal rest seat is prepared in the form of a ____ at the incisal angle of a canine or on the incisal edge of an incisor, with the deepest portion of the preparation apical to the incisal edge | rounded notch |
REST-More advisable in Mn canines | incisal rest |
In the absence of suitable placement rest and rest seats. Incisal rest on multiple Mn incisors maybe considered, use of such rest maybe justified by the following factors: | 1. Anterior guidance
2. Additional stability
3. Such rest can restore defected or abraded teeth |