Instrument Design And Classification

Question 1

What is optimal instrument weight and why?

Answer 1

15 g or less

Light weight design places less stress on hand muscles are acquires less pinch force

Question 2

What is optimal handle diameter?

Answer 2

3/8 inch- Large diameter requires less pitch force

Question 3

Optimal handle texture

Answer 3

Knurling pattern

Increases static friction btw fingers and handle

Question 4

What to avoid when choosing a handle

Answer 4

Heavy, solid handle
Small diameter
Non-textured

Question 5

What is pinch force?

Answer 5

Refers to force used to grasp the handle during instrumentation

Larger handle diameters and light weight requires less pinch force

Question 6

When is a periodontal i strument balanced?

Answer 6

When the working ends are aligned with the long axis of the handle

Ends are centered with the midline of the handle

Question 7

Why is it important for instruments be balanced?

Answer 7

Ensures that finger pressure applied is transferred to the working end for calculus removal

Unbalanced= difficult to use and stresses muscles

Question 8

What is the reason for shank bends?

Answer 8

To facilitate placement of the working end against the tooth surface

Question 9

Characteristics of a simple shank

Answer 9

Will appear straight

For use on anterior teeth

Adequate to reach along the crown and onto the root of wedge shaped anterior teeth

Question 10

Describe complex shank design

Answer 10

Side to side bends
Bent in 2 places

For use on posterior teeth. Large bulky crowns have greater diameter than the roots. Bends allow for adaptation to facial/lingual/proximal surfaces of the root

Question 11

Describe rigid shanks

Answer 11

Remove heavy deposits. Can withstand pressure

Question 12

Describe flexible shanks

Answer 12

Remove small to medium deposits

Enhance tactile info trsnsmitted to fingers

Desireable for explorers, vibrations created when moved over tooth surface irregularities

Question 13

What is the functional shank

Answer 13

Portion of the shank that allows the working end to be adapted to the tooth surface

Begins below the working end and extends to the last bend in the shank near the handle

Question 14

What is the lower shank

Answer 14

Portion if the functional shank that is nearest to the working end; also called the terminal shank

Used for ID of correct working end

Question 15

What is the purpose of an extended lower shank?

Answer 15

Can reach the middle and apical thirds of the root surface

Question 16

What is the use of a simple shank with short functional shank length?

Answer 16

Supragingival used on anterior teeth

Question 17

What is the use of a simple shank with a long functional shank length?

Answer 17

Subgingival use on anterior teeth

Question 18

What is the use of a complex shank with short functional shank length?

Answer 18

Supragingival use on posterior teeth

Question 19

What is the use of a complex shake with a long functional shank length?

Answer 19

Subgingival use on posterior teeth

Question 20

What are some examples of instruments that may be single ended?

Answer 20

Periodontal probe, explore and spatula

Question 21

Which instruments are frequently double ended?

Answer 21

Curetes

May be paired or unpaired

Question 22

What is the difference between paired and unpaired working ends?

Answer 22

Unpaired gave dissimilar working ends, paired have mirror image working ends

Question 23

Features of instrument identification

Answer 23

Design name and design number

Design name is school or person who designed the instrument and the design number identifies the working ends

Question 24

Parts of the working end

Answer 24

Face, back, lateral surfaces (either side), cutting edges (Sharp edge formed where the face and lateral surfaces meet), toe (rounded) or tip (pointed)

Most working ends have two cutting edges

Question 25

What is the significance of instrument cross section?

Answer 25

Determines whether the instrument can be used sub gingivally or is restricted to supragingival use

Question 26

Instrument use for those triangular in cross-section

Answer 26

Limited to supragingival use

Question 27

Instrument use for those semi circular in cross-section

Answer 27

Used supragingivally and subgingivally

Question 28

What are the two classifications of periodontal instruments?

Answer 28

Assessment instruments and calculus removal instruments

Question 29

What are the two types of assessment instruments?

Answer 29

Periodontal probes and explorers

Question 30

What are the three types of calculus removal instruments?

Answer 30

Sickle scalers, curettes and periodontal files

Question 31

What is a periodontal probe?

Answer 31

Slender instrument used to evaluate the health of the gums

Blunt, rod shaped working end

Question 32

What is an explorer?

Answer 32

Used to locate calculus deposits, tooth irregularities and defective restoration margins. Circular in cross-section

Question 33

What are sickle scalers used for?

Answer 33

Used to remove supragingival calculus deposits. Triangular and cross-section has a tip with a pointed back

Question 34

What are curettes used for?

Answer 34

Used to remove supra or sub gingival calculus deposits. Semi circular in cross-section with a toe and a rounded back

Question 35

What is a periodontal file?

Answer 35

Used to crush large calculus deposits. Each working and has several cutting edges