Steps for obturation

Question 1

Step 1

Answer 1

Access cavity preparation

use 330 FC bur or 557 bur, safe ended z bur, taperred diamond bur, #2,4 slow speed round bur

objective: 
SLA to canal orifices, midrtoot or first canal curvature
unroof the completel pulp chamber
pulp chamber tissue removal
conerver tooth structure

Question 2

Step 10

Answer 2

MAF radiograph and final rinse

Radiograph with the MAF at the WL, final rinse with EDTA, Alcohol, NaOCL, Alcohol, then dry canal

Objective:
confirm that the MAF is at the full WL and the canal has been prepped well
Confrim clear and dry canal

Question 3

Step 2

Answer 3

find, explorer and negotatie canal

K files ,8,10,15 used in hand filing or in endo handle
motion by hand filing watch widn and pull out, up down or circumferential filing

Objective:
Identigy all the canals
deteremine canal patency
smooth canal walls
Agitate irrgation solution to dissolve pulp tissue

Question 4

Step 9

Answer 4

apical canal prep

use #10 or 15 file to carefull maintain apical patecny
use step back filing technique to enlarge the apical working length size from #20 glide path to size calculated to MAF

obectives:
maintain canal patency
maintain wl
maitaint original apical foramen position
no canal ledgin zipping or apical transportation

Question 5

Step 3

Answer 5

Preflare and tissue debridement

us 15,20 hedstrome files by hand or in file holder
up down circumferential filing motion around the periphery of the canal

objective
enlarge the canal
canal debridement
reduce cervical triangular dentin to improve SLA to mid root canal

Question 6

Step 8

Answer 6

mid root prep

start with #60 file and in passive balance force technique
continue in crown down method with balance force down to files sizes 55,50,45,40

objective
enlarges midroot canal to blend into coronal prep
continue agitated irrigation and disinfetion of the canal
mid root prep will be even more defined with the next step of apical prep, by hand filing or rotary instrumentation

Question 7

Step 4

Answer 7

coronal prep

gates glidden #2,3,4,
origive opener BR0

objective
enlarge the orifice
enlarge the coronal canal to mid root level size 70
reduce cervical triangular dentin
improve accuracy of working length measurements removing any mid root canal interference
improve depth of irrgation solution penetration

Question 8

Step 7

Answer 8

glide path prep

starting with the IAF gradually increase size of file till goes to WL with #20 file
work files in step back, to a size #40 in watch winding, 1/4 turn pul and circumferential filing
irrigate between each file

Objective
prep path to remove all interferences from orifice to apical terminus of canal
smoooth canal
clear and lcean out pulp tissue by irrgant agitation and file movement
establish smooth glide path to at least #20

Question 9

Step 5

Answer 9

working length radiograph

use at least a #15 file for radiograph
passively place file into canal with moderate resistance near estimated wl disstance
do NOT aggressively work this file in. And remember AT LEAST A #15 FILE

objective
from this radiograph dterimine full length of canal
determine the adjusted or calculated wl from this radiograph
for each canal
obeserve the canal curvatures
note possibilty of additional canal

Question 10

Step 6

Answer 10

apical gauging

use small k files passively to determine apical gauging and canal size

objective
determine aptency file size
determine IAF the first file that binds to WL
estimate MAF which is 3-4 file sizes larger than IAF
MAF will be the largest file size use to clean apical portion of canal at full working length.