instrumentation Flashcards
(53 cards)
1
Q
cutting instruments
A
- excavators
- chisels
- hatchets
- trimmers
2
Q
non-cutting instruments
A
- amalgam condensers
- mirrors
- explorers
- probes
3
Q
parts of hand instruments
A
- blade (nib)
- shank (shaft)
- handle
4
Q
shank
A
- connects handle to the working end of the instrument
- normally smooth, round, tapered
- 1 or more bends to overcome tendency of the instrument to twist
5
Q
blade bevels
A
- can have 1 or more cutting edges
- usually have 1 (primary cutting edge)
- used for planing or scraping walls for prep
6
Q
instrument angle
A
- measured in centigrades
- made by the long axis of the blade and the long axis of the handle
7
Q
3 number instrument formula
A
- width of blade in tenths of mm
- length of blade in mm
- angle of blade from the long axis of the shaft in centigrades (or hundredths) of a circle
8
Q
4 number instrument formula
A
- width of blade in tenths of mm
- angle of the cutting edge form the long axis of the shaft measured in centigrades
- length of blade in mm
- angle of blade from the long axis of the shaft in centigrades (or hundredths) of a circle
9
Q
chisels
A
- used for shaping and smoothing cavity prep walls and floors
- cutting enamel
- straight thrust motion
- subdivisions: straight chisel, curved chisels, bin-angle chisels, enamel hatchets, and gingival margin trimmers
10
Q
hatchet
A
- has beveled side cutting ability
- for refining and smoothing enamel and dentin
- large (CP1247)
- small (CP8/9H)
11
Q
marginal trimmers
A
- used to remove unsupported enamel rods on gingival walls of proximal preps
- similar design to enamel hatchet except blade is curved
- primary cutting edge is at an angle to the access of the blade
12
Q
excavators
A
scooping instruments fro removing carious material, refinement of the internal aspects of the preparation, and establishment of correct anatomical restoration form
13
Q
carvers
A
facilitate the carving and contours of the restorations
14
Q
condensers
A
are used to place and/or condense restorative materials into a prepared cavity prep
- non-cutting
15
Q
4 types of ecavators
A
- ordinary hatchets
- hoes
- angler formers
- spoons
16
Q
periodontal probe
A
- measures 10 mm
skips 4 and 6
17
Q
instrument grasps
A
- modified pen
- inverted pen
- palm and thumb
- modified palm and thumb
18
Q
modified pen grasp
A
- greatest control
- maintains ergonomic positioning of wrist and elbow
- thumb, index, and middle finger hold instrument
- ring finger = fulcrum on nearby tooth
- palm faces away from operator
19
Q
inverted pen gasp
A
- finger position same as modified pen
- but palm faces more toward operator
- used for tooth preps employing the lingual approach to anterior teeth
20
Q
palm and thumb grasp
A
- requires careful use during cutting
- handle placed in palm of the hand and grasped by all fingers
- thumb is free from instrument
- rest is provided by supporting the tip of the thumb on a nearby tooth
21
Q
modified palm and thumb
A
- used when feasible to rest the thumb on the tooth being prepared or the adjacent tooth
- handle held by all 4 fingers
22
Q
finger rest
A
- helps steady the hand during operating procedures
- ring finger on a tooth of same arch and as close to operating site as possible
- the closer the rest areas, the more reliable
- CANNOT be on soft tissue
23
Q
types of handpieces
A
- air driven
- electric motor driven
(both have LED lights to illuminate working field)
24
Q
straight handpieces
A
- used in dental laboratory
- laboratory procedures
(outside of mouth)
25
contra-angle hand piece
3 speed ranges (slow, medium, high/ultrahigh speeds)
26
slow speed RPM
less than 12,000
27
medium or intermediate RPM
12,000-200,000
28
high or ultrahigh speed RPM
more than 200,000
29
electric handpiece motors operate up to
40,000 RPM
30
how can electric handpiece motors reach "high speed" if motor only operates up to 40,000 rpm?
there are attachments that multiply the rotation ratios 5:1 or 4:1
31
air drive hand pieces produce up to _____ watts of cutting power whereas electric handpieces produce ____ watts
20, 60
32
why is extra wattage of cutting power important?
allows constant torque necessary to cut various restorative materials and tooth structure regardless of the load
33
unlike air-driven handpieces, the electric does not _________ or _________ as load is increased
slow or stop (stall)
34
advantages and disadvantages of air-driven hand pieces
35
advantages and disadvantages of electric motor hand pieces
36
high speed handpieces
- best for cutting enamel and dentin
- friction grip burs
- generated heat and must use water as cooling agent
37
slow speed handpieces
- used for removal of carious dentin with slowly rotating round burs
- used for finishing and polishing procedures
- friction grip or latch grip burs
38
kavo quattrocare
- cleans, lubricates, and purges handpiece instruments
- help reduce wear and repairs with increase longevity
- 1 min cleaning cycle
- should be used every use
39
dental burs
- used with handpiece for cutting, smoothing, or polishing tooth or dental materials
- carbide
- finishing
- diamonds
- polishing
- laboratory
40
parts of the carbide dental bur
1. head - working part
2. neck - connection (transmit rotational forces)
3. shank - accepts rotary motion
41
bur shapes influence
end result of the cut surface
42
bur shapes include
- round
- inverted cone
- pear shaped
- straight fissure
- tapered fissure
43
round burs
- spherical
- used for initial entry
- extension of prep
- prep of retention
- caries removal
44
inverted cone bur
- rapidly tapered cone with apex of cone directed toward the bur shank
- head length is about same length as head diameter
- used for undercuts in tooth preps
45
pear shaped bur
- slightly tapered cone with small end of the cone directed toward bur shank
46
straight fissure bur
- elongated cylinder
- can be used for amalgam tooth preps
47
tapered fissure bur
- slightly tapered cone with small end away from shank
- used for indirect restorations
- avoids undercuts
48
bur flutes
- blades with depressed areas between them (flutes)
- high speed can have 6, 8, 10
- slow speed can have 12 to 40 blades
- more blades = smoother prep
49
diamond burs have 3 parts
1. metal blank
2. powdered diamond abrasive
3. metallic bonding material that holds the diamond powder onto the blank
** blank resembles bur without blades
50
diamond particle size is commonly categorized as:
- coarse (125-150 um)
- medium (88-125 um)
- fine (60-74 um)
- very fine (38-44 um)
51
diamond finishing instruments:
- finer diamonds (10-38 um)
- produce relatively smooth surfaces with diamond polishing pastes
52
surface finished of less than ___ um are considered _____________ _________.
1
clinically smooth
53
carbide vs diamond burs
