Canal Prep Flashcards
(27 cards)
Quarter turn clockwise rotation and pull
Turn and pull
Push and pull
Filling
30-60 deg clockwise and counterclockwise movement of the instrument
Watch winding
About 90 degrees clockwise rotation of the instrument and about 270 degrees counterclockwise rotation in slight apical pressure
Balanced force
Steps in root canal prep
Scouting
Early coronal modification
WL determination
Glide path preparation
Canal prep
Apical gauging
Patency
Access prep
Characterized by:
Complete deroofing
Walls slightly divergent
Straight-line access
No damage to walls and floor
Location of all canal orifices
Scouting steps
- Irrigate with naocl 1:5 conc
- Explore the coronal portion of the root canal with #10 to assess depth the instrument may advance passively
- Use #8 for moderate difficulty cases, advancing with watch wind motion toward terminus and assess the WL
- For difficult cases, scout only to the depth instrument may advance, then proceed to coronal flaring
Early coronal modification
Steps
Aka coronal flaring
1. Remove restrictive coronal dentin using orifice opener to entire length of the file
2. Irrigate with NaOcl at 1.5 conc
WL determination steps
- Assemble apex locator according to manufacturers instructions
- Check for connectivity by placing lip hook to clip file. Connectivity should reflect in the visual scale
- Insert IAF at TWL to clip file and the lip hook to the angle of the mouth
- Dry the canal
- Insert IAF into the canal
- Adjust length depending on the reading of the apex locator. Rubber stopper should be at the reference point
- Verify with periapical radiograph
Glide path preparation steps
- Irrigate with NaOCL 1.5 conc
- Explore and shape a root canal at least to a size 15 instrument before the use of NiTi instrument to full WL
- Repeat irrigation
- Recapitulate by inserting a smaller previous file at actual WL to maintain patency
Canal prep steps
- Identify first the rotary files to be used according to approach (crown down, single length or hybrid)
- Use the files with a brushing motion according to its identified approach. Make sure to follow torque and speed recommendation
- Irrigate after each file
- Recapitulate with IAF at actual WL
- Wipe the flutes of rotary files with a clean gauze
Apical gauging steps
- Gauge canal by using MAF equivalent to tip diameter of last rotary file used.
- Push lightly file at WL to check if it moves in an apical diretion
- If the file is snug at WL, take a radiograph of canal with MAF
- If the file advances apically, use a bigger file at actual WL to determine apical diameter
- Use rotary files to prepare canal further based on apical gauging.
- irrigate after each file
- Recapitulate with IAF at actual WL
Patency steps
- Measure size 10 with length 1mm greater than the actual
- Insert into anal and check iff rubber stopper is at reference point
- Irrigate and dry canal with paper point
- If not, check if there is blockage and remove/correct blockage
- Temporize
crown length measurement
Incisal edge to CEJ
Root length measurement
CEJ to apex
Radiographic tooth length measurement
Incisal edge to apex
Tentative working length measurement
Radiographic tooth length - 2mm safety factor)
Radicular length measurement
Tentative working length - 4mm
It is the length of the root canal preparation measured from a suitable coronal reference point to the estimated position of the apical constriction
Working length
Refers to the passive placement of small hand file ISO 10 or smaller, 0.5-1.0mm through the apical constriction during root canal prep
Patency
The aim of this procedure is to prevent blockage of the apical portion of the root canal by debris created during instrumentation
Patency filling
Bur for cutting metallic restoration
Tungsten carbide bur
Bur that cuts ceramic, less fracture
Diamond bur
