preclinical techniques lecture quiz- Instrument design, mirror, principles of instrumentation (weeks 1 and 2 combined set)

What are the detection instruments

mouth mirror, probe, explorer

What is the use of a mouth mirror?

-retraction of lips, cheek, tongue

-illumination

-transillumination (anterior teeth)

-indirect vision

What is the use of a probe

detection instrument used to assess the health of the periodontium

what are the the types of probes

nabers, novatech

what is the design of the probe

- round in cross-section

- blunt tip

- mm markings (calibrations) = 3,6,9,12

What are examples of probes

-NCTI 12 probe (what we have)

- Nabers probe (for furcation detection)

- UNC 12 (1 mm markings)

What is the use of the explorer

detection instrument used to detect decay/ caries and deposits

What is the design of explorers

-wirelike working end

- terminates in sharp point

- round in cross-section

What are examples of explorers

- 3 ES (caries detection)

- ODU 11/12 (calculus)

What are the scaling/ root planing instruments

curette, scaler, hoe, file, chisel

What is the use of curettes

- can be used supra and subgingivally on tooth and root surface

- Removes deposits

What are the types of curettes

universal and area specific (gracey)

universal curettes can be used

anywhere in mouth

area specific (gracey) curettes can be only used in

specific areas of mouth

what's the design of curettes

- rounded back

- rounded toe

- half-circular cross section

what are examples of curettes

-barnhardt 1/2 (universal)

-Gracey 5/6, 11/14, 12/13 (area specific)

What is the use of scalers

remove heavy calculus primarily supragingivally (slightly sub if tissues allow)

What are the types of scalers

-sickle (sickle blade)

-Jacquette (straight blade)

What is the design of scalers

- pointed tip

- triangular in cross section

Examples of scalers

- anterior: NE 128; H6/H7

-Posterior: S 204 SD, IUFW 204, Nevy SCNEV13XE2

What is the use of a hoe

remove large, heavy supragingival calculus

What is the design of a hoe

-single straight cutting edge

-rectangular in cross section

What is an example of a hoe

7K

What is the use of a file

-crush calculus

-Smooth margins of amalgam restorations

What is the design of a file

-multiple, straight cutting edges

-rectangular in cross section

What are examples of a file

- Hirschfeld 3/7 (facial, lingual), 5/11 (mesial, distal)

- Orban 10/12 (facial, lingual), 12/13 (mesial, distal)

What is the use of a chisel

-remove heavy supra gingival calculus

- break anterior bridges of calculus

What is the design of a chisel

-single, straight cutting edge

-rectangular in cross section

What is an example of a chisel

american 22/23, 24/25

What is the working end of an instrument used for

detect, measure, remove

What are possible shapes of instrument handles

round, octagonal

What are the types of handles

long (permanently fixed), cone socket (screw in)

What are the disadvantages of a thin handle

difficult to grasp, greater fatigue

What are the advantages of a thick handle

easier to grasp, reduces fatigue and pinch force

What are the advantages of hollow handles

greater tactile sense, light, less fatigue

What are the disadvantages of solid handles

reduces tactile sense, heavy, greater fatigue

What is an after five shank, its 3 mm longer and used for…

deeper pockets

the straight/simple angulation of a shank is for

anterior use

the angled/ complex angulation of a shank is for

posterior use

What is a flexible shank used for

more tactile sense, remove small surface irregularities and calculus deposits

What is a rigid shank used for

less tactile sense, utilized for strength for removal of large calculus deposits

What are the different cross-sectional shapes of working ends

triangular, rectangular, half circle, cylindrical

What instrument is triangular in cross-sectional design

scalers

What instrument is rectangular in cross-sectional design

hoe, file, chisel

What instrument is half circle in cross-sectional design

curettes

What instrument is Cylindrical in cross-sectional design

explorer, probe

What instrument is pointed in tip design

explorer/scalers

What instrument is blade in tip design

hoe, file, chisel

What instrument is rounded in tip design

curette

What instrument is blunt in tip design

probe

What are the working end parts of instruments

face, lateral sides, back, cutting edges

the cutting edge is formed from

junction of face with sides of working end

How many cutting edges does a curette have

universal-2

Area specific- 1 per end

How many cutting edges does a scaler have

2 per end

How many cutting edges does a hoe have

1 per end

How many cutting edges does a file have

many per end

How many cutting edges does a chisel have

1 per end

How many cutting edges does a explorer have

none

How many cutting edges does a probe have

none

Describe a fulcrum

the support or point of rest of a finger on a tooth surface, on which the hand pivots when activating an instrument

What is the purpose of a fulcrum

stabilize hand, provide leverage, guide instrument

Intraoral placement options of fulcrum

on or next to tooth of operation, arch of operation, on tooth structure

extraoral placement options of fulcrum

palm up- resting on lateral aspect of mandible

palm down- resting on lateral aspect of mandible

fulcrum pressure

moderate-firm

Definition of insertion/exploring stroke

stroke used to place instrument on tooth surface prior to final adaptation and activation

Where do you insert when trying to remove a deposit

below the deposit

Where do you insert for subgingival scaling

base of the sulcus (pocket)

Where do you insert for supragingival scaling

cervical (closest to the gumline or below) to the deposit

What is the pressure for insertion/exploring stroke

very light

What is the hand motion you make during insertion/exploring stroke

Move apically (toward apex/root) or rock toward your thumb

define adaptation

how the instrument is placed in contact with the tooth surface

what is the purpose of adaptation

tactile sensitivity, minimal gingival displacement, minimize tissue trauma

during adaptation, you adapt the _______ of the working end to the tooth surface

1/3

Define angulation

angle formed between the instrument face and the tooth surface (>45 degrees but <90 degrees)

What is the ideal instrument face-to-tooth angulation

60-80 degrees

What is the ideal insertion angulation

0

When working with a probe, what is the guideline for angulation

working end kept parallel to the tooth surface being explored

When working with an explorer on posteriors, what is the guideline for angulation

terminal shank is parallel to the tooth surface being explored

When working with an explorer on anteriors, what is the guideline for angulation

upper shank is parallel with the tooth surface being explored

When working with a scaler on posteriors, what is the guideline for angulation

terminal shank is parallel to tooth surface being instrumented (scaler)

When working with a scaler on anteriors, what is the guideline for angulation

upper shank is parallel to tooth surface being instrumented (scaler)

When working with gracey curettes on posteriors, what is the guideline for angulation

terminal shank is parallel to tooth surface being instrumented

When working with gracey curettes on anteriors, what is the guideline for angulation

terminal or upper shank is parallel to the tooth surface being instrumented (gracey curette)

When working with universal curettes on posteriors, what is the guideline for angulation

terminal shank is parallel to the tooth surface being instrumented (universal curettes)

When working with universal curettes on anteriors, what is the guideline for angulation

upper shank is parallel to the tooth surface being instrumented (currette)

definition of activation/working stroke

moving the instrument along the tooth surface. coronal stroke (vertically)

pressure of activation/ working stroke

moderate to firm

Technique of activation/working stroke

pull stroke moves instrument coronally (Up) /rock toward fulcrum finger, activated using a rocking motion

Subgingival activation strokes for facial and lingual surfaces

epithelial attachment to a position coronal to the CEJ

Subgingival activation strokes for proximal surfaces

epithelial attachment to contact point

Supragingival activation strokes for facial and lingual strokes

gingival margin to occlusal or incisal edge

Supragingival activation strokes for proximal surfaces

gingival margin to contact point

Steps for activation/working step

1. modified pen grasp

2. fulcrum

3. insert gently

4. adapt end 1/3

5. angle 60-80 degrees

6. apply pressure to fulcrum and tighten grasp

7. activation stroke to remove deposit

8. pause, relax, and repeat

Parts of the mouth mirror

handle, shank, working end (face and back)

Uses of mouth mirror

indirect vision, retraction, illumination, transillumination

mouth mirror can be used to retract

lips, cheeks, tongue

mouth mirror can be used to illuminate which is using the mirror to do what

project light onto unlit surface

mouth mirror can be used for transillumination which is using the mirror to do what

reflect light through teeth

The mouth mirror uses the _______ _____ grasp with your _________ hand

modified pen, non-dominant