Lecture 3 Flashcards
Placement of dam:
2 teeth behind the tooth of interest to the contralateral incisor
Ist molar hole
second largest hole
premolar hole
3rd largest hole
Clamp size for tooth #15
3
of points of contact you should have with clamp:
4
line up bow:
parallel to the lines on the dam
lubricant we use
Every Man Jack shaving cream
to get rubber dam bw teeth
Reach waxed tape - very thick
Hook this side on the dam first:
top
On which tooth does the first clamp attach?
2 behind the tooth you are working on and one on the actual tooth as well.
Function of bow clamp:
Retracts gingival tissue for facial/cervical
4 parts of clamp
bow (arch), pinch, wing, jaws
W2:
Premolare
W3:
Flat jawed
W8:
normally erupted max molars
W8a:
small/partially erupted molars (jaws angle down)
212:
double bowed clamp - class 5 lesion, small lower teeth
on which side is the clamp more gingival, lingual or buccal?
buccal to retract tissue more to fill the Class V restoration
How do you have to punch the hole for the 212 clamp for a Class 5 cervical lesion?
slightly out of alignment to the buccal
Operative teeth that need to be isolated:
quadrants
Endodontics teeth that need to be isolated:
single tooth
Steps previous to dam placement:
- anesthesia
- Check inter-proximal contacts
- Check occlusal contacts
- shade selection in esthetic restoration
6.
7. - Select retainer
- Retainer is ligated (attach floss)
T or F? Always restore tooth to an anatomically perfect tooth if restoring.
F. Reproduce the restoration as the occlusal contact wee before you started
Dam lubricants we can use:
water soluble/ vaseline
Steps for placement:
- selection of teeth to be isolated
- select retainer
- cut orifices
- lubricate rubber dam
- place clamp
- pass ligature flow through dam most posterior orifice
- stretch rubber dam over the retainer sealing it on the distal (double punched sometimes)
- Distribute orifice on each tooth
- Wedjet to fix anterior end (rubbery material)
- place fram and napkin
- Floss dam
- Inversion of dam
Dam removal:
- cut septa bw teeth
- remove ant/pos anchorage
- remove dam and fram
- verify all has been removed (lie dam flat on surface)
When might we not use dam
anterior, if we do - canine to canine
Ligature use benefits:
- keep dam inverted
- improve access
- controls filtration
When not to use dam:
- partially erupted that clamp won’t hold on to
- some 3rd molars
- very malpositioned teeth
- pts w/ asthma
- psychological reasons
- latex allergies (non-latex is available)
Isolation types
cotton rolls, gauze, iso-shield, saliva ejectors, spandex, retraction cords
when to use retraction cords:
sub gingival caries and ?
When is RD isolation evaluated?
every practical procedure
T or F? Push RD through the teeth from posterior to anterior.
F. Anterior to posterior
To cut, plane and cleave tooth structure:
Hand instruments
Instruments used to cut and shape tooth structure in the school classification:
A series
Examples of instruments used to cut and shape tooth structure:
hatchets, hoes, chisels, and spoons
Instruments used to place restorative materials in the school classification
B series
Examples of instruments used to place restorative materials
amalgam condensers and plastic instruments
Instruments used to shape and finish restorative materials in the school classification:
C series
Examples of instruments used to shape and finish restorative materials:
Hollenback carvers, cleoid discoids and various other carvers
Primary cutting edge may be:
monobeveled or bibeveled
connects blade to handle:
shank
T or F? All hand instruments have secondary cutting surfaces.
F.
What do the numbers represent in Black’s 3 Number Formula?
width of blade in tenths of a millimeter, length of blade in millimeters, angle of the long axis of the blade (degrees centigrade)
1st digit of Black’s classification system of 15 is how long?
1.5 mm
25 degrees centigrade corresponds with how many degrees?
90
Black’s 4 # formula
width of blade in tenths of a millimeter, angle of cutting edge of the blade with the handle (degrees centigrade), length of blade in millimeters, angle of the long axis of the blade (degrees centigrade)
What is the 2nd digit in Black’s 4 digit numbering system?
angle of cutting edge of the blade with the handle (degrees centigrade)
Rotary cutting instruments:
burs, diamonds, and drills (end cutting inst. only)
Which is more effective as a side cutting instrument. bur or drill?
bur
What is a bur?
multi bladed rotary milling cutters
direction of bur spinning
counter clockwise (when viewed form cutting end)
How are burs classified?
shape and diameter of the cutting end of the bur
Burs can have as many as ___ blades, but usually have.
40, 6-8
Which part the bur adapts to the handpeice?
shaft (friction grip, latch type)
We primarily use these burs:
330 (pear) and 245 (long inverted cone)
plural depth we most often need:
1.5-1.6mm (330 = 1.6mm)
Parallel sided bur, #’ed 55 1/2 to 60, multipurpose bur:
straight fissure bur
cross cuts (notches), 556-560, to improve cutting efficiency (not really anymore), same basic shape as straight bur:
cross cut straight fissure bur
33 1/3 -40, develop retentive features, smooth walls,sharpen angles of prep, sides of bur converge toward shank:
inverted cone bur
168-171, develop initial stages of prep and tapered wall forms, sides of bur converge toward end of bur:
tapered fissure bur
1/16th - 11, used to develop retentive features and to remove caries
rough bur (1/4 round and 1/2 round in this course)
diamond particles are attached to a metal black - size and shape of the diamond particles determine the abrasiveness:
diamond bur
How are sextents divided?
bw the canines and the 1st premolars
Where are the marginal ridges of ant teeth?
m and d borders of the lingual surfaces
Common cause of fissures:
lack of fusion of the enamel of adding dental cusps or lobes
axial wall:
wall adjacent or nearest to the pulp chamber or pulp canals, approx parallel to the long axis of the tooth
What is the wall of the occlusal portion of a prep?
pulpal wall
Shape of lingual and facial walls for amalgam placement:
parallel or convergent for retention
Shape of lingual and facial walls for resin composite:
can be divergent since bonding will occur to dentin or enamel
T or F? The line angles for bonded restorations must be well defined.
F. may not be well defined, often rounded
Another name for margins:
cavosurface angles
What are cavosurface angles?
jxn of a cavity wall and an external tooth surface
T or F? in a normal, healthy individual the clinical down is typically smaller than the anatomical.
T
On which surfaces do Class I lesions occur?
facial, lingual, an occlusal
Class I lesions most often occuur on these teeth:
lateral incisors
These ant teeth rarely get Class I lesions.
Canines
T or F? A lesion in a pit on the facial surface of an anterior tooth is a Class I restoration.
T
Class 5 lesions may include involvement of what type of tooth structure?
cementum, dentin, and/or enamel
Do Class 5 lesions include lingual surface or only refer to buccal and labial surfaces?
Both
Bonded, tooth-colored restorations require neither:
mechanical or undercut retention.
The shape or outline of the cavity prep:
cavity form
The shape of cavity prep needed to obtain access for instruments:
conveinience form
The shape of cavity prep needed to provide retention for the material:
retention form
The shape of cavity prep required to resist stress on the restoration and the tooth from forces:
resistance form
Blacks’ steps of cavity preparation:
- Establish outline form
- Obtain resistance form
- Obtain retention form
- Obtain convenience form
- Remove remaining carious dentin
- FInish enamel walls and cavosurface margins
- Clean the prep
T or F? Improperly placed restoration may lead to tooth fracture of the tooth restored.
T
How is retention obtained?
mechanical shaping and/or bonding procedures
Why are unsupported enamel overhangs more prone to fracture after restoration placement?
polymerization shrinkage
Preferred hand instrument metal:
stainless steal (iron, chromium {corrosion resistance}, carbon {hardness}, and maybe nickel)
The working end of the blade should be within:
2-3mm of the axis of the handle
Does a longer or shorter blade require more force to be used?
longer
The name for when an instrument is angles so as to bring the working end within 2-3mm of the long axis of the handle:
contra-angled ( 2 or more angles)
Diameter of standard metal handle:
1/4 inch (6.4mm)
T or F? Larger handled instruments are said to be more ergonomic.
T
Black called all cutting instruments used for tooth preps:
excavators
Up to how many angles may shanks have?
4
Instruments in which the blade and cutting edge are on a plane with the long axis of the handle:
hatchet
Instruments with a blue that is either aligned with the handle, slightly angled, or curved from the long axis of the handle, with the working end at ta R angle to the handle:
chisel
What type of instrument is a Wedelstaedt?
chisel
This type of instrument has a cutting edge that is at a R angle to the handle with a blade at an angle greater than 12.5 centigrades from the long axis of the handle than a chisel:
hoe
The blade of a hoe must be at an angle to the long axis of the handle greater than __ degrees (not centi-grades)
45 degrees
The blade of a chisel must be at an angle to the long axis of the handle less than ____ degrees.
45 degrees (12.5 centigrades)
T or F? The cutting edge of a spoon is parallel to eh handle of the instrument.
T
This instrument has a blade that is curved and the bevel for the cutting surface edge at the end of the blade is always on the outside of the curve:
gingival margin trimmer
This instrument has a blade rotated 45 degrees from the plane oath long axis of the handle:
off-angle hatchet
Which angle of the off-angle hatchet is meant of use?
acute angle
On which side of the blade is the bevel in an off-angle hatchet?
back
Puling strokes with a double-ended hoe are done with this end:
beveled end or end with distal bend
Pushing strokes with a double-ended hoe are done with this end:
contra bevel end or end with mesial bevel
Are most cutting instruments single or double beveled?
single
What instrument is useful for placing retention points in some direct girl (gold foil) filings?
bi-beveled cutting edge of off-angle hatchet
When is the 3-numbered system used?
instruments in which the primary cutting edge is at a R angle to the long axis of blade
In margin trimmers a cutting edge angle of greater than __ centigrades is intended for distal gingival margins:
90
In margin trimmers a cutting edge angle of __ centigrades or less is intended for mesial gingival margins:
85
a blade with its primary cutting edge on the side of the blade toward the handle:
beveled
a blade with its primary cutting edge on the side of the blade away from the handle:
contrabeveled
Is contrabeveld a mesial or distal bevel?
mesial
These are designed to plane enamel and dentinal walls and margins:
hatchets, hoes, chisels, and gingival margin trimmers
The flat end of the nib of a condenser:
the face
These are used to place amalgam:
condensers, carvers, and burnishers
A hollow cylindrical instrument that is filled with amalgam:
amalgam carrier
Is vertical or lateral condensation used to push amalgam against the prep floor?
vertical condensation
Is vertical or lateral condensation used to push amalgam against the vertical wall?
lateral condensation
Which require more force, small or large condensers?
large
How do we condense resin material?
We don’t. It doesn’t actually get condensed. Trick question
What size condenser should you use to pace a resin composite filling?
the largest that will fit in the area
What should you use to contour a convex amalgam contour?
concave-shaped carver
What should you use to contour a concave amalgam contour?
convex
claw shaped:
cleoid
These are good for carving occlusal surfaces:
cleioid-discoid carvers
What is a Walls no. 3 carver used for?
occlusal surface
What is the Hollenback no. 1/2 carver used for?
occlusal, proximal, and axial surfaces
This is used for carving proximal amalgam surface near the inter proximal contact areas and occlusal, proximal, and axial surfaces (also for place and shaping resin composite and packing cord:
interproximal carver (ICP)
What is no. 14L used for?
to carve proximal surface, or carving convex facial and lingual surfaces of very large amalgam restorations, also for removing amalgam overhangs from completely set amalgam
What should you use for carving lingual concavities of anterior teeth?
discoid carver
What should you use for occlusal surfaces of posterior resin composite restorations?
cleoid and discoid carvers and the hoe-shaped end of the walls no. 3 carver
Function of burnishers:
to make shiny or lustrous, esp by rubbing
What is PKT# burnisher used for?
placing direct restorations
What is the ovoid burnisher useful for?
final condensation of amalgam and ate initial shaping of the occlusal anatomy in amalgam
What are the beaver tail and ovoid burnishers useful for?
burnishing margins of cast old restorations
What instrument should you use to shape metal matrix bands?
burnisher
What should you use to pinch off freshly condensed amalgam at the margins?
large burnisher
These are used to “bend” cast gold near the margin to narrow the gap bw the gold and the tooth:
burnishers
What instrument should you use to close a marginal gap bw a gold restoration and the tooth?
narrow burnisher (beavertail burnisher)
This instrument is used to carry and shape tooth-colored restorative materials:
plastic instrument
What inst. should you use to place and contour a large, anterior resin composite rest or veneers?
plastic inst, with a large, slightly curved, paddle-shaped blade
What instrument should you use for placing and contouring large, anterior resin composite restorations or veneers:
Almore Gold Microfil instrument
What instrument should you use for placing a dam, shaping composite, and packing cord?
no. 1-2 plastic instrument
Selection of a rigid or flexible cement spatula is dependent upon:
the desired viscosity of the cement and personal preference
Should you use a rigid or flexible spatula for luting cement (glass ionomer and zinc phosphate)?
flexible
The very short, thin spatula is used for:
cavity liner such as CaOH liners
Is the blade sharp or dull if there is a glint?
dull
How do you sharpen chisels, hatchets, hoes, and margin trimmers?
cutting-edge bevel is placed flat against a flat stone, pushed or pulled so that the acute cutting angle is moved forward - heavy force forward, less force on back stroke
The bevel of chisels, hatchets, hoes, and margin trimmers should be at what angle from the face of the blade?
45 degree angle
T or F? The primary bevel should always be flat against the stone and the face of the blade up when sharpening.
T
What will happen if you make the angle of your blade too acute?
will dull quickly
Working end bevels of chisels, hatchets, hoes, and margin trimmers should be at __ degree angle to the face of the blade.
45 degree
How do you sharped a spoon, discoid carver, or cleoid carver instrument?
rotate instrument as blade is advanced the stone with bevel against the stone
While sharpening chisels, hatchets, hoes, and margin trimmers, the cutting edge of the blade should be kept ___ to the direction of the stroke and the bevel ____ with and against the surface of the stone.
perp, parallel
Another name for oscillating flat stone:
hone
T or F? A hone should be oiled before use.
F. it may thicken on the instrument and form a coating
What type of stone should you use for sharpening?
flat, white Arkansas stone or fine synthetic sharpening stone
Ideal placement of light source while with a pt in a chair:
behind and directed just to the side of the operator’s head and into the mirror
What size mirror is usually used for adults?
no. 4 (7/8-inch diameter) and no. 5 (15/16-inch diameter)
What size mirror for constricted areas?
no. 2 (5/8-inch diameter)
Most common explorers:
shepherd’s hook or no. 23 explorer, or cowherd explorer
When is a cowhorn explorer helpful?
better access for exploring proximal surfaces
These explorers are good for proximal surfaces:
cowhorn and no. 17
This instrument is useful in placing or removing items used to confine amalgam for condensation:
hemostat
Types of hemostats:
Halstead mosquito straight and curved
2 different types of grasps for holding instruments:
pen grasp and palm/ palm-thumb grasp
Which grasp allows for more flexibility of movement?
pen grasp
This grasp is for limited movement with controlled power:
palm-thumb grasp
When is 2-handed instrumentation needed?
make refinements of a prep more precise
Features of the pen grasp:
engaged by the end, not the side, of the middle finger/ ring finger is braced against the teeth
What types of motions are made using the palm-thumb grasp?
side-to-side, rotating, or thrusting movements
Features of the palm-thumb grasp:
grasped much nearer to its end, thumb braced against teeth
Occasion to use he palm-thumb grasp:
Class 3 prep that has a lingual access or with the Wedelstaedt chisel, usually for facial access in posterior and anterior operations, and occasionally for lingual access
Describe chopping motion:
in the direction of the working end of the instrument or parallel to the long axis of the blade
At what angle should you hold the blade for scraping?
bw 45 and 90 degrees to the surface being scraped
What is the orientation of the axis of the bur in relation to the long axis of the handpick with a straight handpiece?
they are the same
When are straight handpieces used?
adjustments to remove prostheses or adjusting and replacing a cast gold or ceramic restoration prior to insertion
Low-speed contra-angle is good for:
shaping and polishing with abrasive disks and impregnated rubber polishers or refining tooth preps
How many RPMs does the typical slow-speed have?
500-15,000 rpms
Typical RPMs of a high-speed:
180,000 (up to 500,000)
What type of handpicks do most dentists in the U.S. use?
air-turbine
The use of this type of high-speed is rapidly growing:
electric (200,000 rpm - very efficient)
What is the ideal speed of a handpiece for cutting enamel?
200,000
Are penetration through enamel and extension of the cavity outline more efficient at high or low speed?
high
T or F? High-speed should only ever be used with both water and air.
F. Can be slowed and used with only air coolant and a gentle brushing or painting motion.
2 types of contra-angles:
friction grip chuck and latch-type chuck
Another term for bur locking mechanism:
chucking mechanism
What type of chuck does the high-speed employ?
friction-grip bur
Order smallest to largest: latch type bur, friction-grip, and straight handpiece.
friction-grip, latch type bur, and straight handpiece
Most common bur for excavating cavity prep since 1947.
tungsten carbide bur
3 parts of bur:
head, neck, and shank
T or F? The angle of the cutting blade in burs is usually acute.
F. usually not acute
The angle of the cutting blade in burs is usually in the range of ___ degrees.
90
___-bladed burs are the most common.
6
Do most burs in dentistry have a positive or negative rake?
negative
What does negative raking of the bur provide?
increases life expectancy of bur and provides the most effective performance in low and high-speed ranges
Does a positive rake angle produce a more or less acute edge angle?
more
When would you use positive rake angles?
to cut softer, weaker substances, such as soft carious dentin
There are __ basic tooth prep burs.
5
Who made the specification standard for burs?
American National Standards Institute/ ADA
The American National Standards Institute/ ADA standard lists both:
the US numbers and the ISO (international standards organization) numbers
5 main bur types:
round, inverted cone, straight fissure, tapered fissure, pear-shaped
A bur with a diameter of 0.8mm will have an ISO size of:
008
A bur with a diameter of 1.0 mm will have an ISO size of:
010
These burs are good for making very smooth cuts in tooth preps, for adjusting occlusion in enamel or of a restoration, and for corning and finishing restorations:
trimming and finishing burs
Which have more blades, trimming and finishing burs or tooth-prep burs?
trimming and finishing burs
T or F? the greater the number of blades, the smoother the cut surface that can be attained.
T
Ho does the number of necessary blades vary?
with the diameter of the bur
trimming and finishing burs typically have how many blades?
8-12, 16-20, or 30
These are straight-side tapered burs with a safe non-cutting end so that the end will rest not he tooth surface without cutting tooth structure and allowing for contouring of the adjacent restoration:
8, 16, or 30 blades
When should you use diamond burs:
bonded restorations
T or F? Diamond burs are an acceptable substitute for carbide.
T
Would you want a diamond bur with a heavy or fine-grit diamond surface for contouring and polishing esthetic restorations?
fine-grit
T or F? Airdent (SS White) can be used with resin restorations.
T
Air-abrasion units are used for:
opening fissures, some cavity preps, and to facilitate repair of existing restorations with bonding technology
Air-abrasion technology has recently come out with a curtain of water aroudn the spray of ____
alumina particles
What are sonic and ultrasonic technologies used for in dentistry?
endo and conservative cavity preps
What type of loupes provide the finest magnification/
telescopes
The focal distance for loupes should be in this range:
10 -14 inches
What diopter range is recommended for loupes?
2-4-diopter range
T or F? It is believed that bond strength of restorations is increased with the use of a dam/
T
What gauge rubber dam material is suggested?
extra-heavy gauges (0.012 inch)
Why is extra-heavy gauge dam material better?
less likely to tear, better seal to teeth, and retract tissues more effectively
How can you extend the shelf life of dams past a year?
refrigerate
2 types of dam punches:
Ainsworth-type and Ivory (Hereaus Kulzer)
What type of frame holder can you use with a dam if you know an x-ray will be needed?
plastic, radiolucent
2 types of dam frames:
Metal Young frame and Plastic Nygaard-Ostby frame
Which dam frame is outside the dam and which is placed inside the dam, Metal Young frame and Plastic Nygaard-Ostby frames?
Metal Young frame - outside of dam
Plastic Nygaard-Ostby frame - inside
These are used to place the clamp for the dam:
Ivory forceps
Which type of forcep allows more freedom for rotation, Ivory or Stokes?
Stokes
2 types of dam forceps for clamp placement:
Ivory or Stokes
3 types of clamps:
winged, wingless, butterfly
W:
wingless clamp
no w:
winged clamp
Most clamps can act as both:
rubber dam retainers or as rubber dam and gingival tissue retractors
T or F? The butterfly clamp can act as both a rubber dam retainers or as rubber dam and gingival tissue retractors.
F. retractor only
T or F? The clamp makes the seal.
F. The dam does
What determine the stability of a clamp?
distance bw the points of a jam, along with the stiffness of the bow of the clamp
Clamps should only be expanded to this width:
pass over the facial and lingual heights of contour of the tooth
Why shouldn’t the floss be left under the dam?
causes leakage or it is in the way
Should waxed or unwaxed floss be used with dam placement?
waxed
These are used to plane rough enamel, amalgam, or resin composite contact so that the floss will pass through without shredding and so that the dam can be flossed through without tearing:
interproximal contact disk
Should plain metal interroiximal disks be used adjacent to gold casting?
No, can cut into the gold
What type of lubricant is preferred for the dam?
water-soluble (Velvachol water-miscivle vehicle)
Why avoid petroleum based lubricants with dam placement?
can impede bonding procedure and make inversion of the dam more difficult
How can you protect the MIP contacts before a restorative procedure to an occlusal surface?
coat with a clear light-cured resin or varnish
Hole punch size to use for clamped molars:
5
Hole punch size to use for unclamped molars:
4
Hole punch size to use for premolars:
3
Hole punch size to use for canines:
3
Hole punch size to use for MCI’s:
3
Hole punch size to use for MLI’s:
2
Hole punch size to use for MI’s:
2
Dam placement for posterior restorations:
all teeth around to the central or lateral incisor on the opposite side of the same arch
Dam placement for anterior restoration:
first premolar to the first premolar on the opposite side of the arch
Why are the 1st molars exposed for anterior restorations?
to provide anchorage for the dam and to leave adequate working room
Where should the hole be punched in a dam for a Class V restoration?
about 1mm facial to the spot
What is it called when discomfort due to a clamp on tissue disappears within 1 minute?
pressure anesthesia
What should you do immediately after clamp placement?
Stabilize clamp with finger until you are sure the clamp is secure on the tooth
T or F? Inversion of the dam creates a negative pressure by the tongue and cheeks.
F. Positive pressure
What happens when negative pressure is created under the dam?
saliva is trapped in the field bc the valve closes
What happens when positive pressure is created under the dam?
pushes the valve more tightly against the tooth so that no flooding of the field occurs
Does positive or negative pressure seal the dam more tightly?
positive
What can you use to invert the dam?
floss or air
How can you protect the dam when working with a handpiece in the vicinity of the dam?
wedge
When is a second clamp used?
to retract the dam below a margin that is near, or below, the level of the gingival crest
What can leaving a small piece of the dam in the mouth cause?
inflammation, gingival abscess, or loss of period supprt
Plus side to using bite block:
pt can relax muscles of jaw
What other clamp is usually used along with the butterfly clamp?
posterior clamp
What tissue level is a mini flap procedure confined to?
keratinized gingival tissue ( and kept as short as possible)
How should the incision be directed when preforming gingival relaxation?
directed slightly into eh papilla and then vertically
Finger pressure should be maintained for how long after gingival relaxation?
2 min
T or F? Cavit hardens when it comes into contact with moisture.
T
Other methods of isolation:
Isolite, Svedopter, Hygoformic saliva ejcetor, Vac-ejector, Absorbent paper and cotton products
Another name for parotid duct:
Stenson’s duct
stay tat this depth while prepping
1.5mm
prep to this level
where white meets the yellow
diaper and length of 330 bur
diameter= .8mm length = 1.6
Amalgam requires this type of prep:
parallel or convergent walls
Indirect restorations require;
divergent walls
Is the 330 bur used in both the high and low speed?
yes
2 handpicks for he slow speed:
contra-angle and slow speed handpiece(?)
