ENDO816: Cleaning and Shaping

Mechanical Preparation

hand/rotary files

Chemical Prepation

irrigation solutions

What is the purpose of irrigation solutions?

flush out debris

lubricate canals

dissolve tissues

prevent/remove smear layer

antimicrobial

T/F: C/S reduces the irritants, not removing them

TRUE

Working Length (WL)

distance between a fixed coronal reference point (e.g. a cusp tip) and an apical reference point (e.g. the apical constriction)

Initial Apical File (IAF)

first file to bind @ the estimated WL

What is the first file to bind at the estimated WL?

IAF

Master Apical File (MAF)

largest file went to the corrected WL

What is the largest file went to the corrected WL?

MAF

What the minimum MAF?

#30 or F2

Estimated WL

radiographic length - 1 mm

Type A Constriction

Traditional single constriction

Type B Constriction

tapering constriction

Type C Constriction

Multiconstricted

Type D Constriction

Parallel Constriction

What are the methods for WL determination?

radiographic determination

use of anatomical average in literature (0.5-1.00 mm)

tactile sensation

moisture on paper point

electronic apex locator (EAL)

Which method of WL is not the best?

tactile sensation

Which file is often used to get estimated WL?

15 K File

T/F: Assume root resorption for older patients

TRUE

EAL Problems

irrigants

vital tissues/ blood

metallic restorations

T/F: you cannot use EAL with those who have a pacemaker

FALSE

Watch-Winding (Balanced Force Technique)

back and forth CW/CCW rotation with light apical pressure

Which instrument movement utilized light apical pressure with both CW and CCW rotation?

Watch-Winding

Which instruments utilize Watch-Winding?

Handfiles

Reaming

file binds to the wall and rotates CW 180-360 degrees to plan walls and enlarge the canal space

Which instrument movement enlarges canal space by binding to the wall and rotating CW?

Reaming

Which instruments utilize Reaming?

patency files

Filing

pressing file laterally against the wall and withdrawing along path of insertion

Which instrument movement is withdrawn and pressed laterally against the wall?

Filing

Which instruments utilize Filing?

S1 and S2

Rotary

in and out pecking motion for 3-5 times

Rotary files must not exceed ___ seconds

3-5

Danger Zone

area near the furcation

T/F: selectively remove dentin away from the danger zone when coronally flaring

TRUE

Recapitulation

process used during RCT to ensure the root area is cleaned out thoroughly and free of debris

What files is used to recapitulate?

small file #10 or #15

T/F: Recapitulation is used to enlarge the canal walls

FALSE

What motion is Recapitulation is used?

reaming

Circumferential Filing

used for canals that are larger and not round

What technique is used for Circumferential Filing?

step-back technique

Protaper gold uses a ___ technique

modified crown-down

Which protaper fold files work at the cervical 1/3 ONLY

SX Files

T/F: SX files engage the dentin

FALSE

What is D0 for SX file?

0.19 mm

What is the length of SX file?

19 mm

What is the cutting length of SX file?

14 mm

What is D6 of SX file?

0.5 mm

What is D7 of SX file?

0.7 mm

What is D8 of SX file?

0.9 mm

What is D9 of SX file?

1.1 mm

What is D14 for SX file?

1.2 mm

Which Protaper Gold file works at the cervical to middle 1/3?

Shaping Files (S1 and S2)

What is the color of S1?

purple

What is color of S2?

white

What is D0 of S1?

0.17 mm

What is D0 of S2?

0.20 mm

What is cutting length of S1 and S2 ?

14 mm

What is the maximal flute diameter of S1 and S2?

1.2 mm

Which Protaper Gold file works at the apical 1/3 with at the WL?

Finishing File

What is the D0 and Taper of F1?

0.20 mm

7% taper

What is the D0 and Taper of F2?

0.25 mm

8% taper

What is the D0 and Taper of F3?

0.30 mm

9% taper

What is the D0 and Taper of F4?

0.40 mm

6% taper

What D0 and Taper of F5?

0.50 mm

5% Taper

The dentin mud and debris is moved ____ in Protaper Gold?

coronally

Commonly used endodontic irrigants

Sodium Hypochlorite (NaOCl)

Chlorohexidine (CHX)

EDTA

In NaOCl, which dissolve tissue?

Cl ion

How much NaOCl is used per canal at MUSC?

3-5 cc

Advantages of Sodium Hypochlorite (NaOCl)

antimicrobial

tissue dissolving

inexpensive

Solution typically travels ____ head of the tip

< 1 mm

Chlorohexidine (CHX) properties

pH 5.5-7

bactericidal

bacteriostatic

non-tissue dissolving and does not remove smear layer

Bactericidal of CHX works at __ concentrations

high

Bacteriostatic of CHX works at __ concentrations

low

CHX interactions with NaOCl

parachloroaniline (PAC)

CHX interactions with EDTA

white ppt salt of CHX

Cationic Charge of CHX

electrostatically binding to negatively charged surfaces such as bacteria --> damaging outer layer of cell wall --> permeable

EDTA liquid solution %

15-17%

T/F: EDTA removes the smear layer

TRUE

What needle is best?

side vented

Ideal Properties of Canal Irrigants

germicide

fungicide

non irritating

stable in solution

anitmicrobial

low surface tension

active in tissue, blood, etc

non toxic

does not stain tooth

deactivated in culture medium

removes smear layer

no adverse effects with dentin

no adverse effects with sealers

user friendly

inexpensive

Irrigation is ___ from the WL

1-2 mm

Irrigation flow rate

4 ml/min

Which Irrigant is used between files

NaOCl

Final Rinse

EDTA --> NaOCl --> Saline --> dry