Isolation and File ID Flashcards
what does the rubber dam protect from
patient from swallowing or aspirating instruments and materials
the dental dam is defined as:
standard of care
effective isolation crucial to:
- RCT success
- patient protection
- provider protection
what is one of the basic objective of successful contemporary RCT
the elimination of micro orgranisms within pulpal spaces
can you eliminate micro organisms in the presence of saliva
no it is impossible
what can ensure the absense of saliva in the surgical field
only a properly applied dental dam
failure to eliminate salivary leakage by proper placement of the rubber dam creates:
salivary contamination
what can salivary contamination cause and how
life threatening cellulitis by introducing additional micro- organisms which can greatly complicate the infection
what will cause NaOCl to leak into the mouth as you irrigate
if saliva is not effectively sealed by dam placement
what is 8.3% NaOCl commonly used for
flushing out debris and cleaning the prepared canal system
what are latex dams available in
black, white, blue, green color in various weights and thickness
- non latex dams also available in the clinic
which type of rubber dam frame should you select
one which is radiolucent so you can leave it in place when taking radiographs
how many teeth should be isolated with the rubber dam
isolate only the tooth to be treated
should you take the rubber dam off and frame off when taking radiographs
no
what is the “butterfly” labial clamp useful for
most anterior teeth and even some premolars
how are clamps without wings used
placed first on the tooth with the RD later stretched over the clamp and tooth
what tooth is rubber dam clamp #212 designed for
anterior tooth
how do you place the clamp
- once dam is securely placed below the height of contour of the tooth, push the dam off the wings of the clamp
where should the clamp rest
at the cervical line below the height of contour to be adequately retained
when is it difficult to retain clamps over the height of contour
with young or partially erupted teeth
what happens when the dam has not been released from the wings of the clamp
leaks
even after the dam is released from the wings of the clamp, it may be necessary to use some type of ________ around the tooth to ensure isolation
sealing agent to caulk
what sealing agent can be used to caulk around the tooth
Oraseal by Ultradent
when would you use a caulk- seal agent
if you have any idea that leakage might occur
what do you do if you are unable to achieve 100% effective isolation of the tooth to be treated
- provisionally restore tooth to obtain isolation base
- clinical crown lengthening procedure
- refer to endo specialist
- if still cant treat, consider alternate treatment modality
if you cannot place an effective rubber dam:
you cannot do a RCT on the tooth
a badly broken tooth requiring RCT is covered with ____
hyperplastic gingiva
what must you do to a badly broken tooth before RCT
build up
how can you excise the gingiva to cover the badly broken tooth
electrosurgery, laser, or conventional surgery
what may excision of gingiva do
expose sufficient tooth structure to be able to place a clamp and isolate with dental dam to allow for RCT
what is the split dam technique
cant place a clamp on the tooth so the dam is stretched over neighboring teeth and the rubber dam over the tooth of interest is sealed by the use of oraseal
what are the types of endo files
- hand files
- reciprocal files
- vortex file .25/.12
- vortex blue files
why are there different types of files
- each file type has unique attributes
- each file type can benefit us in a specific way when used correctly
- each type is important to consistent RCT success
describe the stainless steel hand file
- takes a sharper edge
- is fairly flexible up to #20
- can be pre- curved easily to negotiate very curved canals- retains the shape
- increases geometrically in stiffness as diameter increases
- efficient when used by hand
- separates if overused or abused usually with some warning
describe nickel- titanium motor driven
- edge not as sharp- motor driven for efficient shaping
- is extremely flexible - super elastic but difficult to pre curve
- has nearly perfect shape memory - will not hold a curve
- works efficiently in engine driven handpieces
- separates if overused or abused usually with NO warning
what are SS K- type hand files made of
twisted tapered stainless steel wire having a square, triangular, or diamond shaped cross section
basically SSK hand files are:
screws
continual clockwise rotation will cause an SSK hand file to:
-screw itself to and out the end of the root or
- become locked in dentin and fracture
what are hand files essential for:
- scouting the canal - #10 or #8
- creating a glide path (#10 to patency and #15 to WL only
- bypassing a ledge, blockage or separated instrument
- gaining length
what hand files will be used for most cases
10 and #15
when would you use larger sized files
serial step back
what sizes to hand files come in
0.08 - 0.14
what are the measurements of hand files
the tip of the diameter in hundredths of a mm
what is the sequence of hand files
white,yellow,red,blue,green,black
from .45 to 0.80 and again 0.90 to 1.40
what is the last file size before the increments of sizes go up 0.1
0.60
what mnemonic helps you remember the sequence of hand files
“Will You Really Be Going Back”
hand files are supplied in ________ lengths,
21,25, and 31mm
no matter which length is supplied, the fluted portion of the file is ____ long
16mm
all standardized K-type hand files are
0.02 taper
what does 0.02 taper mean
from D0 to D16 the diameter increases regularly by 0.02mm in diameter for each 1mm that one travels from D0 to D16
what is the color sequence of hand files starting at #15
white, yellow, red, blue, green, black
how much greater does the diameter become on a file every 1mm back
0.02mm
what happens to a SS K hand file if bent too sharply in an angular fashion or distorted in any way
it cannot be bent back to a useful shape and must be discarded before placing in a tooth
when can hand files break/separate within the canal
excessive engagement during clockwise rotation especially in smaller sizes
what are the safest intra- canal instruments
hand files
hand files give us the greatest ______ of all intra canal shaping instruments and serve as _____ and basic instrumentation to negotiate _______
greatest tactile sense; pathfinder, canal curves and blockages
what motion are hand files used in
watch winding motion
what motion is used to remove hand files
circumferential filing from length
- press against alternate walls of canals and pull back for a filing motion
dont go to the next larger file until:
you have worked the smaller file to the point that the next larger file goes to the desired length without pushing
never place a ____ file in a curved canal
straight
what percent of canals are curved
all of them to some degree
what should you do when entering canal
gently curve all hand files
try to _________ the greatest curve you observe in the radiograph of the canal
match or slightly exceed the greatest curve
what will happen if you slightly exceed the curvature of the canal
the file will track the inner wall of the curve and be conformed to the actual curve of the canal
if you place a straight file in a curved canal what happens
the file will track the outer wall of the the curve and gouge the canal at that point creating what we call a ledge
what happens if you create a ledge
it may be difficult or impossible to regain the true canal as subsequent file insertions tend to more easily follow the path of the ledge
forcing a file from a ledge will lead to:
a root perforation or separated instrument and probable failure of the case
when a scouting file fails to advance but is loose in the canal:
do not push but realize that the canal takes a bend at this point
- remove the scouting file and place a 45 degree bend in most terminal flutes
- use this in a light probing motion to indicate
-the path of the curve as in picking a lock
- once the path is discovered to patency it may be smoothed and carefully enlarged to #15 as a glide path
what are the only way to scout a canal
hand files
what are the only way to bypass a ledge or separated instrument
hand files
what are the only way to negotiate and smooth a tight curve to smooth the glide path or to regain lost length
hand files
what are most engine driven reciprocal and rotary files made of
nickel titanium and related alloys
what are engine driven reciprocal and rotary files used for
the ability to stay centered in the canal was basic in their introduction
- based on their quality of performing in a super elastic manner
- easily follow a smoothyl created glide path and immediately return to their designed shape when stress is removed
what are wave one gold files
motor driven reciprocal files
what do motor driven reciprocal files do
push material ahead of the file
- used in 3 passes to prevent pushing debris out the end of the root where it would cause inflammation
what size is the small wave one gold files
0.20/.07
what do 6 black bands indicate on the .25/.12 vortex Ni-Ti rotary file
12 taper
what is the maximum flute diameterin the .25/.12 vortex rotary file
1.20mm size #129
the .25/.12 may not be appropriate to enlarge a smaller canal and may need to be carefully used to a depth less than the maximum flute diameter to avoid:
excessive root structure or possible strip perforation of the root
- about the depth of 12-14mm only
what are the sizes of the vortex blue rotary files
.25/0.04 through .45/.04
what size is the vortex rotary file
.25/.12
what is the size of the patency file
.10/.02
what is the size of the glide path file
.15/.02
we will be using vortex blue files of the following sizes
-.25/.04
- .30/.04
- .35/0.4
- .40/.04
- .45/.04
- .50/.04
larger than #50 we will do ____ with _____
serial step back; hand files
vortex blue files tip sizes are identified by:
the color of the ring
the taper of the file is identified by the number of:
black bands x 2
what sequence are the vortex blue files used in
25-30-35-40-45
what is the intended use of the barbed broach
rotated in canal to entangle and remove vital pulp organ
describe the barbed broach
- SS hand instrument with plastic handle
- a round wire which is barbed by scoring and prying a tag of metal away from the long axis of the wire
- if broach becomes bound within the canal or forced around a canal curvature, it will routinely break upon removal attempt
when are barbed broach instruments recommended
large, straight canals
when is the reamer useful
by advancement and rotation in straight canals
why are reamer instruments dangerous in curved canal
ledging is the usual result
the tip of the reamer is ____ in nature
cutting
how is the reamer made
by twisting a square or triangular wire but the angle between the long axis of the instrument and the cutting blade is small so it is ineffective when used in a filing motion
describe the hedstroem file
- a ground round wire
- cuts aggressively on pull stroke
- vulnerable to rotation
- prone to fracture
- used by faculty
how are reamers manufactured
by twisting a tapered triangular SS blank
fewer flutes are created than _____
K type files
reamers cut only upon ____
rotation
reamers are ineffective with a ____ motion
filing
why are reamers dangerous
they tend to stray away from natural canal
how are K type files manufactured
by twisting a tapered square or rhomboidal SS blank
how are K type files effective
when used with a rasping (pulling) motion
K type files are _____ prone to fracture
less
K type files tend to follow natural canal when ____
pre-curved
what type of files do we use: Reamers, K-type files, Hedstrom files
K-type files
how are hedstrom files manufactured
by machining (grinding) tapered round SS blank
hedstrom files have a ________ when used in a filing motion
aggressive dentin removal
why are hedstrom files weaker
due to machining
if hedstrom files are used in a rotational manner:
they are very easily broken
