Armamentarium Flashcards
How many mm increase in taper for every diameter of the instrument
0.02mm
21mm lenth is used for ___ tooth
Molars
25mm length of instrument is used for __ tooth
anteriors
28 and 30mm length of instrument is used for __ tooth
canines
40mm length os instrument is used for __
endodontic implants
tip angle of the instrument should be ___ angle
75 + or - 15 degrees
working blade shall begin at tip ___ and extend ___mm up to the shaft __
tip (D1)
16mm
shaft (D2)
color coding of instrument
pink
grey
purple
white
yellow
red
blue
green
black
classification of endodontic instrument
exploring
smooth broach and endo explorers
classification of endodontic instrument
debriding or extirpating
barbed broaches
classification of endodontic instrument
cleaning and shaping
reamers and files
classification of endodontic instrument
obturating
pluggers, spreaders and lentulospirals
classification based on method of use
GROUP 1: hand-operated endodontic instruments
- broaches and rasps
- k-type reamers and files
- hedstroem files
classification based on method of use
GROUP 2: low speed instruments with latch type attachment
- gates - glidden drills
- peeso reamers
classification based on method of use
GROUP 3: engine -driven instruments
- rotary NiTi intruments
- reciprocating instruments
classification based on method of use
GROUP 4:
sonics and ultrasonics
the earliest endodontic instruments used to extirpate pulp and debris from the canal
broaches and rasps
it is one of the oldest intracanal instruments
short handled instrument meant for single use only
barbed broach
does not cut dentin but can effectively be used to remove cotton or paper points which might have lodged in the canal
broach
broach should not be inserted into the root canal unless the canal has been enlarged to a size No. ___
25reamer/file
used of barbed broach
extirpate of entire pulp tissue
removal of cotton or paper points lodged in the canal
removal of necrotic debris and foreign material from canal
it is free of barbs, previously used as a pathfinder
smooth broach
difference of rasp and broach
barb size is larger in broach than rasp
canal enlarging instruments made from stainless steel
K-type reamers and files
used to ream the canals
reamer
has trianglular bland and lesser number of flutes than file
reamer
has 1.5-2.5 cutting blades per mm of their working end
k-file
This file was made because square blank of files results in total decrease in the instrument flexibility
It has a rhombus shade with two acute angles and two obtuse angles
K-flex file
Similar to k-flex file except it has triangular cross section, provides more flexibility and an ability to resist fracture
Flexo file
Made by removing the sharp cutting edges fom the tip of the instrument
Made up of NiTi and cuts during anticlockwise rotary motion
Flex-r file/ roane file
Has flutes that resembles successively triangles set on one another
Made by cutting soiral grooves into round, tapered steel wire in the same manner as wood screws are made
Tends to fracture in torquing action since it lacks flexibility
Hedstroem file
Modifications of H-file
Has noncutting safety side of the length of the blade
Safety hedstroem file
Modifications of H-file
Designed with two spirals for cutting blades, forming double helix design
S-file
Modifications of H-file
Variant of H-file
Its cutting edge are at an acute angle to long axis of the file
When used in curved canals, flutes on the inner edge collapse, so no dentin is removed. On the outer edge, flutes open, filling the dentin on outer curvatures
A-file
Modifications of H-file
It is machined from round ss steel wire by cutting two superficial grooves to produce flutes in double helix design
Unifile
Modifications of H-file
Made from specially treated ss so have amazing stiffness and strength to be used for difficult and calcified canals
Has better buckling resistance than k-file
C-file
Traditional engine driven instrument which have flame-shaped cutting point mounted on long thin shaft attached to a latch-type shank
Flame cuts laterally
Are side cutting instruments with safety tips
Safety design is that its weakest part lies at the junction of the shank and shaft, so it if jams against the canal fracture occurs at the junction of shank and the shaft bot not at the tip
Gates-glidden drills
Modified gates glidden drills, which are more flexible and can be rotated continuously in a handpiece through 360deg
Flexogates
Rotary instrument mainly used for postsPace preparation when gutta-percha has to be removed from obturated root canal
Peeso reamer
Commonly used NiTi rotary instrument in endodontics
55NiTinol
60NiTinol
A phase of a NiTi alloy, on cooling, transformation induced in alloy occur during shear type of process ___
Martensitic phase
Martensite shape can deformed easily to a single orientation by process ___ when there is flipping over type of shear
Detwinming
First use of NiTi in endodontics was reported in ___ year
1988
Lattice of NiTi allow is simple, referred as ____
Austenite or parent phase
It is the working area of file
It is the surface with the greatest diameter which follows the flute as it rotates
Blade
Angle formed by cutting edge and cross section taken perpendicular to long axis of the tooth
Rake angle
If angle is formed by leading edge and surface to be cut is obtuse, rake angle is ____
Positive or cutting
If angle formed by leading edge and surface to be cut is acute, rake angle is ____
Negative or scraping
It is the area between the flutes which projects axially from central axis, between flutes as far as the cutting edge
Radial land/ marginal width
Surface area of land which is reduced to s certain extent to reduce frictional resistance
Relief
It is the angle formed by cutting edge with the long axis of the file.
This angle is important for determining which file technique to use
Helical angle
It is the distance between point on leading edge and corresponding point on leading edge
It shows number of threads per unit
Pitch
Generation of niti rotary file
Passive cutting radial lands, fixed tapers of 4% and 6% over the length and negative rake angles for scraping
1st generation
Profile, GT rotary file, Quantec, HERO642, light speed
Generation of niti rotary file
Active cutting edges, variable taper, fewer instruments needed to prepare the canal
2nd gen
Protaper universal, K3, protaper gold, hero shapers
Generation of niti rotary file
Improvements in NiTi metallurgy, reduce cyclic fatigue and file separation
3rd generation
K3XF, twisted files, profile GT X series, hyflex CM
Generation of niti rotary file
Reciprocation movement (bidirectional movement, single file concept)
4th gen
Wave one, SAF, reciproc
Generation of niti rotary file
Offset center of mass, mechanical wave of motion travelling along the length of the file, swaggering effect of file
5th gen
REVO-S, protaper next, one shape
Most commonly used irrigating canals
Sodium hypochlorite
Its main activity is toward smear layer removal because of its chelating power which makes it effective in removing the inorganic components of dentin
EDTA
Ethylene tetraacetic acid
A method of filling and sealing a tooth with root canal material
Obturation
Most commonly used sealer
Has proven ability toy to seal against microorganism
Zinc oxide eugenol
Physiological saline or isotonic saline
The same isotonicity as the body’s blood
NSS
Used to dry the root canal after preparation and irrigation
Used to dry thorougly the canal before sealing
Absorbent paper points
A thermoplastic filling that is heated and then pressed into the tooth canal
Used together with ZOE to seal up the canal
Gutta percha points
Metal instrument used for packing root canal fill material in order to make room for additional material
Endodontic spreader
