Final Exam Review Flashcards
what is working length?
how long the root canal system is from incisal/occlusal reference point to the minor apical constriction
what is a patency file?
a very small file, usually size 10, that is used to keep the apical constriction open without widening it
what is the initial apical file?
the first file that binds the minor apical constriction at working length
what is the master apical file?
2-3 file sizes larger than the IAF; it goes to WL passively and stops at WL
what is straight line access?
straight preparation of the canal until the first curvature or the apical third
what are the major and minor constrictions?
the minor constriction is considered the “apical stop”
what are the GG bur sizes?
- GG #2 = 0.7
- GG #3 = 0.9
- GG #4 = 1.1
what is the taper of a regular endodontic file?
0.02mm
what hand file design is the most efficient dentin cutting file we use in endodontics?
hedstrom because it has the most positive rake angle (60 degrees), meaning it is the most efficient at shaving and cutting
what are the two basic ways a file can move in the canal?
rotational and linear
describe watch-winding file movement. what is it’s function in the canal preparation process?
- reciprocating, back and forth (clockwise/counterclockwise) rotation of the instrument in an arch and is used to negotiate canals and to work files to place
- used for mid-root prep and apical prep
describe the step-back filing technique. what is it’s function in the canal preparation process?
- start with the IAF
- determine WL
- set first 3 files to WL
- set each additional file back 1mm
- using the watch-winding movement with 4-8 cycles per file, work your way up through the files using passive gentle touch pressure only, returning to the IAF between each successive file, and irrigating between each file
- repeat as necessary
- used for apical prep
describe the balanced force technique. what is it’s function in the canal preparation process?
- the file is placed to length, rotated clockwise 1/4 turn to engage the dentin, followed by a counterclockwise rotation 3/4 turn with apical pressure to cut and enlarge the canal
- considered the most effective hand instrumentation technique
- used for mid-root prep and apical prep
describe circumferential filing movement. what is it’s function in the canal preparation process?
- the file is placed into the canal and withdrawn in a directional manner sequentially against the mesial, distal, buccal, and lingual walls
- used for pre-flare and for canals that are larger and/or not round
- not very effective beyond the coronal third of the canal
describe anti-curvature filing. what is it’s function in the canal preparation process?
- GG drills and laterally cutting niti orifice shapers are used directionally in an anticurvature fashion to selectively remove dentin from the bulky wall (safety zone) toward the line angle, protecting the inner/furcal wall (danger zone) coronal to the curve
- used for coronal flare to preserve the furcal wall in the treatment of molars
open apex case: a tooth with a WL of 22mm and the apical forament has a large diameter of size #30. describe the concerns with this case and how you would proceed to prepare and obturate this case (include instruments and sizes of instruments you would use, and length of the instruments usage, and the obturation and length used and technique of obturation)
normal routine case: tooth #19, you are going to obturate the 20mm WL distal canal using warm vertical condensation. describe the preparation dimension of the distal root you will prepare for this type of obturation (include distal canal dimensions for this case)
name and purpose of use
D16 endodontic explorer used to explore and locate canal orifices, or to aggressively dislodge calcifications
name and purpose of use
- glick plugger and placing instrument
- plugger end is used for the removal or condensation of gutta percha
- paddle end is used for placement of materials such as temporary restorations
name and purpose of use
- D11 T handled spreader used to laterally compact and adapt GP and create space for accessory cones
- you can also use finger spreaders (red for MAF <40, blue for MAF >40)
which of the following is a k-file and which is a reamer? what is the difference?
- k-file on the left (more flutes)
- reamer on the right (less flutes, also similar to rotary fluting)
hedstrom file
how do you correctly orient a butterfly clamp, and what are of the mouth are they used for?
- the tall end should be toward the lingual, and the short end should be toward the buccal
- anterior regions
what is the correct orientation of the rubber dam frame?
the open end should be toward the patients nose
what is wrong with this isolation setup?
the rubber dam is not released from the wings
describe the final irrigation steps used at the UUSOD
- EDTA 30 seconds
- alcohol rinse
- NaOCl 30 seconds
- alcohol rinse
- master cone fit (tug back)
- paper point dry
what does EDTA stand for, and what does it do?
- ethylenediaminetetraacetic acid
- chelator used for the removal of the smear layer (removes inorganic components and leaves organic tissue elements intact)
what does NaOCl stand for, and what does it do?
- sodium hypochlorite (aka bleach)
- flushes debris from the canal, dissolves vital and necrotic tissue, antimicrobial, and lubrication