SEM EVALUATION OF SMEAR LAYER REMOVAL BY TWO

DIFFERENT SINGLE FILE SYSTEM ALONG WITH VARIOUS

IRRIGATING SOLUTIONS - AN INVITRO STUDY

OBJECTIVES:

 To compare smear layer removal using single file system, Hyflex EDM and Wave

One Gold.

 To evaluate smear layer removal ability of Qmix, Naocl and EDTA.

METHODOLOGY:

A total of Sixty single rooted human mandibular premolars which

showed no caries or any developmental defects were used in this study. ISO size #15 K file

was used for working length determination of each root canal. Before instrumentation, the

specimens were divided into two group of 30 teeth each. Under Group A - thirty teeth were

prepared using Hyflex EDM file. Under Group B – thirty teeth were prepared using

WaveOneGold files. Again after instrumentation the specimens were further subdivided

according to irrigants used under Group A into three subgroups A1-Naocl, A2-EDTA & A3-

Qmix. Under Group B it is subdivided into three subgroups B1-Naocl,B2-EDTA & B3-

Qmix. Then the prepared teeth were split along the longitudinal axis into two halves and they

are used for further analysis. The samples were then examined and photographed using a

scanning electron microscope.

RESULTS:

Result of this present study revealed that the scores for smear layer removal were

significantly lesser in Wave One Gold- Qmix group(B3) when compared with other groups.

There was significant difference between coronal and the middle third, while there is no

significant difference between the apical third of the root canal.

CONCLUSION:

1. WaveoneGold group has better smear layer removal ability than Hyflex EDM group.

2. Qmix group showed lesser score, where smear layer removal is better than the Naocl and

EDTA group.

3. In all the groups there was increased smear layer removal at the coronal and middle third

when compared to the apical third of the root canal.

Key words : WaveOneGold, Hyflex EDM, EDTA, Qmix & SEM analysis.
 INTRODUCTION

The success of endodontic treatment depends on both instrumentation and irrigation . Root canal

therapy is done to eradicate microbes and to provide three dimensionally seal to the tooth. 48

Instrumentation is done either through hand filing or rotary , when compared with hand filing rotary

produces more debris.

To achieve complete disinfection of the root canal system chemomechanical debridement is used.

Root canal instrumentation produces a layer of organic and inorganic material which contain

bacteria and their by -products. It is made up of very small particles of mineralized collagen matrix

which is spread over the surface to form a layer known as smear layer.

The first researchers to describe smear layer on the surface of instrumented root canals were

Mccomb and Smith.56 Smear layer prevent the penetration of intracanal medicaments into the

dentinal tubules and influence in adaptation of root canal filling materials. 48 Elimination of smear

layer from the root canal walls is highly important to obtain long term endodontic success.

HyFlex EDM are the only endodontic instruments manufactured with an EDM process. HyFlex EDM,

mainly composed of martensite and R phase, revealed peculiar structural properties, such as

increased phase transformation temperatures and higher hardness when compared with

conventional manufactured HyFlex CM.

In WaveOne (WO) NiTi file system, a single NiTi (M-Wire technology) file is used in a reciprocating

handpiece to completely prepare the canal to an adequate size and taper, even in narrow and

curved canals. The specially designed NiTi files work in a reverse “balanced force” action using a pre-

programmed motor to move the files in a back and forth “reciprocal motion”. The motor is

programmed such that the counter clockwise movement is greater than the clockwise movement;

three reciprocating cycles complete one reverse rotation. 55

 During root canal treatment irrigation plays a major role in the successful debridement and

disinfection .

Sodium hypochlorite (NaOCl) , chlorhexidine (CHX) and EDTA are the common root canal irrigants

used widely. Unfortunately, no irrigating solution is capable of acting both on organic and inorganic

elements of the smear layer.

QMIX irrigating solution has been introduced as an root canal irrigant. Qmix is a new irrigating

solution which contains EDTA, CHX, cetrimide and a detergent, as it’s composition. The pH of Qmix

is slightly above neutral. It also has both antimicrobial properties of CHX and the smear layer

removing properties of EDTA. The addition of CHX to cetrimide before adding of EDTA generally

prevents any precipitation formation.

Both Hyflex EDM and WaveOne Gold are single file system with different rotary movements. 68 The

aim of the present in vitro study was to evaluate the smear layer removal efficacy using single file

system with three different irrigating solutions..

MATERIALS AND METHODS

Armamentarium:

 Sixty extracted single rooted premolar.

 15 K-file (DENTSPLY Maillefer; Ballaigues, Switzerland)

 Hyflex EDM file (Coltene/Whaledent, Switzerland)

  WaveOneGold file (DENTSPLY Tulsa Dental Specialties Inc., Tulsa)

 2.5% sodium hypochlorite irrigating solution (Prime dental PVT LTD India)

 EDTA

 Qmix 2in 1 irrigating solution (DENTSPLY Tulsa ,USA)

 Endomotor (X Smart plus) (DENTSPLY)

 SEM analysis machine. (SEM-S-3400N-HITACHI)

SELECTION AND PREPARATION OF THE SAMPLES

A total of Sixty single rooted human mandibular premolars which showed no

caries or any developmental defects were used in this study. Teeth were extracted for orthodontic

purpose and it has been approved to be used for invitro research. The teeth were then stored in 10%

formalin until use. The teeth were decoronated and roots were standardized using a diamond disc to

13mm in length. ISO size #15 K file was used for working length determination of each root canal.

Before instrumentation, the specimens were divided into two group of 30 teeth each. Under Group

A - thirty teeth were prepared using Hyflex EDM file. Under Group B – thirty teeth were prepared

using WaveOneGold files.

Again after instrumentation the specimens were further subdivided according to irrigants used

under Group A into three subgroups A1-Naocl, A2-EDTA & A3-Qmix. Under Group B it is subdivided

into three subgroups B1-Naocl,B2-EDTA & B3-Qmix.

The experimental groups are as follows:

A1 Naocl (10 teeth)

GROUP A- Hyflex EDM files (30 teeth) A2 EDTA (10 teeth)

A3 Qmix (10 teeth)

 B1 Naocl (10 teeth)

GROUP B- WaveOneGold (30 teeth) B2 EDTA (10teeth)

B3 Qmix (10 teeth)

EVALUATION BY SCANNING ELECTRON MICROSCOPY

The prepared teeth were split along the longitudinal axis into two halves and they are used

for further analysis. The root was then dehydrated in the ascending alcohol series for 24

hours . Then, the specimens were left dry overnight and then mounted on copper stubs. The

samples were then examined and photographed using a scanning electron microscope. Then

the photo micrographs were taken at 2000x magnification at coronal , middle and apical

thirds of the root canals using the SEM analysis software (Smart SEM User Interface).

CRITERIA FOR SMEAR LAYER EVALUATION:

The smear layer was scored according to the criteria given by Hulssman et al 1997.

 Score 1: indicates no smear layer, and all dentin tubules are open and clean.

 Score 2: indicates a small amount of smear layer, and some dentin tubules are open.

 Score 3: indicates a homogenous smear layer covering the root canal wall, and only a few

dentin tubules are open.

 Score 4: indicates a complete root canal wall covered by a homogenous smear layer, and no

dentin tubules are open.

 Score 5: indicates a heavy, non-homogenous smear layer covering the complete root canal

wall.

STATISTICAL ANALYSIS

Data obtained were obtained systematically in Microsoft Excel spreadsheet. The dataset was

subdivided and distributed and presented as graphs and tables. Statistical analyses were done using

a personal computer with Social Sciences software (SPSS version 22, USA). Normality distribution of
the data was analyzed and statistical tests were used to find out the statistical significance of the

results obtained.

RESULTS

The result of the present study showed that the, distribution of smear layer scores in (A1) (Hyflex

-Naocl) group were 4(20.0% ) and 5(80.0%) in the apical third of the root canal, in the middle third of

the root canal the scores were 4(50.0%) and 5(50.0%) and in the coronal third of the root canal the

scores were 4(80.0%) and 5(20.0%) (table 1 and graph 1).

The distribution of smear layer scores in (B1) (WaveOne Gold – Naocl) were 4(40.0%) and 5(60.0%)

in the apical third of the root canal, in the middle third of the root canal the scores were 3(20.0%)

and 4(80.0%) and in the coronal third of the root canal the scores were 3(60.0%) and 4(40.0%) (table

2 and graph 2).

The distribution of smear layer scores in (A2) (Hyflex -EDTA) were 3(70.0%) and 4(30.0%) in the

apical third of the root canal, in the middle third of the root canal the scores were 2(10.0%) and

3(90.0%) and in the coronal third of the root canal the scores were 2(70.0%) and 3(30.0%) (table 3

and graph 3).

The distribution of smear layer score in (B2) (WaveOne Gold – EDTA) were 3(80.0%) and 4(20.0%) in

the apical third of the root canal, in the middle third the scores were 2(10.0%) and 3(90.0%) and in

the coronal third of the root canal the scores were 2(70.0%) and 3(30.0%) (table 4 and graph 4).

The distribution of smear layer score in (A3) (Hyflex – Qmix) were 2(10.0%) and 3(90.0%) in the

apical third of the root canal, in the middle third the scores were 2(40.0%) and 3(60.0%) and in the

coronal third of the root canal the scores were 2(90.0%) and 3(10.0%) (table 5 and graph 5).
The distribution of smear layer score in (B3) (WaveOne Gold – Qmix) were 2(40.0%) and 3(60.0%) in

the apical third of the root canal, in the middle third the scores were 1(20.0%) and 2(80.0%) and in

the coronal third of the root canal the scores were 1(70.0%) and 2(30.0%) (table 6 and graph 6).

The mean smear layer score in (Hyflex- Naocl) group were 4.2(0.4), 4.5(0.5) and 4.2 (0.4) in the apical

, middle and coronal third of the root canal. The mean smear layer score in the Waveone Gold –

Naocl group were 4.4(0.5), 3.8(0.4) and 3.8(0.4) in the apical, middle and coronal third of the root

canal respectively. There was satistically significant difference at the middle and coronal third

between the groups (p value = 0.0215 and 0.0089). whereas there was no significant difference at

the apical third between the groups (p value = 0.2314) (table 7 ).

The mean smear layer score in Hyflex – EDTA were 3.6 (0.4898), 3.2(0.6), 2.6(0.4898) in the apical,

middle and coronal third of the root canal. The mean smear layer score in the Waveone Gold – EDTA

were 3.3(0.4582), 2.6(0.4898), 2.5(0.5) in the apical, middle and coronal third of the root canal

respectively. There was satistically significant difference at the middle third between the groups (p

value = 0.029). whereas there was no significant difference at the apical and the coronal thirds

between the groups (p value = 0.187 and 0.383) (table 8).

The mean smear layer score in Hyflex – Qmix were 2.9 (0.3), 2.6(0.4898) and 2.1 (0.3) in the apical,

middle and coronal third of the root canal. The mean smear layer score in Waveone Gold – Qmix

were 2.6 (0.4898), 1.8(0.4) and 1.3 (0.4582) in the apical , middle and coronal third of the root canal

respectively. There was statistically significant difference at the middle and coronal third between

the groups ( p value = 0.0089 and 0.0089). whereas there was no significant difference at the apical

third between the groups (p value = 0.112) (table 9).

The difference between the mean smear layer score in the Hyflex group using Naocl irrigating

solution and Waveone Gold group using Naocl irrigating solution method in the middle and in the

coronal third of the root canal was statistically significant difference among the two groups (P =
0.0039 and 0.0255). There is no significant difference among the groups at the apical third (P =

0.091) (table 10).

The difference between the mean smear layer score in Hyflex group using EDTA irrigating solution

and Waveone Gold group using EDTA irrigating solution method in the apical and in the coronal third

of the root canal was not statistically significant (P = 0.1074 and 0.3445). There was significant

difference among the two groups at the middle third (P = 0.0192) (table 11).

The difference between the mean smear layer score in Hyflex group using Qmix irrigating solution

and Waveone Gold group using Qmix irrigating solution method in the apical third of the root canal

was not statistically significant (P =0.1271). There was significant difference among the two groups at

the middle third and at the coronal third of the root canal (P = 0.0018 and 0.0006) (table 12).

TABLES AND GRAPHS

Table 1: Distribution of smear scores (in %) in the apical, middle and coronal thirds of

the root canal in the Naocl, HYFLEX EDM group.

Smear layer
Apical third Middle third Coronal third
score
1 - - -
2 - - -
3 - - -
4 2(20%) 5(50%) 8(80%)
5 8(80%) 5(50%) 2(20%)
Graph 1: Distribution of smear scores in the apical, middle, and coronal thirds of the

root canal in the Naocl, HYFLEX EDM group.

100%
90%
80%
70%
60% score 5
50% score 4
40% score 3
30% score 2
20% score 1
10%
0%
Apical
Middle
Coronal

Table 2: Distribution of smear scores (in %) in the apical, middle, and coronal thirds of

the root canal in the Naocl, WaveOne Gold group

Smear layer score Apical third Middle third Coronal third

1 - - -
2 - - -
3 - 2(20%) 6(60%)
4 4(40%) 8(80%) 4(40%)
5 6(60%) - -

Graph 2: Distribution of smear scores in the apical, middle, and coronal thirds of the

root canal in the Naocl , WaveOne Gold group

 100%
90%
80%
70%
60% score 5
50% score 4
40% score 3
30% score 2
20% score 1
10%
0%
Apical
Middle
Coronal

Table 3: Distribution of smear scores (in %) in the apical, middle, and coronal thirds of

the root canal in the EDTA , Hyflex EDM group.

Smear layer score Apical third Middle third Coronal third

1 - - -
2 - 1(10%) 7(70%)
3 7(70%) 9(90%) 3(30%)
4 3(30%) - -
5 - - -

Graph 3: Distribution of smear scores in the apical, middle, and coronal thirds of the

root canal in the EDTA, HyflexEDM group

100%
90%
80%
70%
60% score 5
50% score 4
40% score 3
30% score 2
20% score 1
10%
0%
Apical
Middle
Coronal
Table 4: Distribution of smear scores (in %) in the apical, middle, and coronal thirds of

the root canal in the EDTA , WaveOne Gold group

Smear layer score Apical third Middle third Coronal third

1 - - -
2 - 1(10%) 7(70%)
3 8(80%) 9(90%) 3(30%)
4 2(20%) - -
5 - - -

Graph 4: Distribution of smear scores in the apical, middle, and coronal thirds of the

root canal in the EDTA , WaveOne Gold group

100%
90%
80%
70%
60% score 5
50% score 4
40% score 3
30% score 2
20% score 1
10%
0%
Apical
Middle
Coronal

Table 5: Distribution of smear scores (in %) in the apical, middle, and coronal thirds of

the root canal in the Qmix , Hyflex group

Smear layer score Apical third Middle third Coronal third

1 - - -
2 1(10%) 4(40%) 9(90%)
3 9(90%) 6(60%) 1(10%)
4 - - -
5 - - -
 Graph 5: Distribution of smear scores in the apical, middle, and coronal thirds of the

root canal in the Qmix , Hyflex group

100%
90%
80%
70%
60% score 5
50% score 4
40% score 3
30% score 2
20% score 1
10%
0%
Apical
Middle
Coronal

Table 6: Distribution of smear scores (in %) in the apical, middle, and coronal thirds of

the root canal in the Qmix , WaveOne Gold group

Smear layer score Apical third Middle third Coronal third

1 - 2(20%) 7(70%)
2 4(40%) 8(80%) 3(30%)
3 6(60%) - -
4 - - -
5 - - -

Graph 6: Distribution of smear scores in the apical, middle, and coronal thirds of the

root canal in the Qmix , WaveOne Gold group

 100%
90%
80%
70%
60% score 5
50% score 4
40% score 3
30% score 2
20% score 1
10%
0%
Apical
Middle
Coronal

Table 7: Mean smear layer score in Hyflex – Naocl and Waveone – Naocl gold group

Hyflex - Naocl WaveOne gold – p value

Group Naocl Group
(Mean ± SD) (Mean ± SD)
Apical 4.2(0.4) 4.4(0.5) 0.2314
Middle 4.5(0.5) 3.8(0.4) 0.0215*
Coronal 4.2(0.4) 3.8(0.4) 0.0089*
#
Wilcoxson signed rank test, *Statistically significant

Table 8: Mean smear layer score in Hyflex - EDTA and WaveOne Gold - EDTA group

Hyflex - EDTA WaveOne Gold -

group EDTA group p value
(Mean ± SD) (Mean ± SD)
Apical 3.6(0.4898) 3.3(0.4582) 0.187
Middle 3.2(0.6) 2.6(0.4898) 0.029*
Coronal 2.6(0.4898) 2.5(0.5) 0.383
#
Wilcoxson signed rank test, *Statistically significant
Table 9: Mean smear layer score in Hyflex – Qmix and WaveOne Gold – Qmix group

Hyflex – Qmix WaveOne Gold -

group Qmix group p value
(Mean ± SD) (Mean ± SD)
Apical 2.9(0.3) 2.6(0.4898) 0.112
Middle 2.6(0.4898) 1.8(0.4) 0.0089*
Coronal 2.1(0.3) 1.3(0.4582) 0.0089*
#
Wilcoxson signed rank test, *Statistically significant

Table 10: Mean smear layer score in Hyflex – Naocl and WaveOne Gold - Naocl

group

Hyflex – Naocl Waveone Gold -

group Naocl group p value
(Mean ± SD) (Mean ± SD)

Apical 4.2(0.4) 4.4(0.5) 0.091

Middle 4.5(0.5) 3.8(0.4) 0.0039*

Coronal 4.2(0.4) 3.8(0.4) 0.0255*

#
Mann Whitney Test, *Statistically significant

Table 11: Mean smear layer score in Hyflex - EDTA and WaveOne Gold - EDTA

group.

Hyflex - EDTA WaveOne Gold – EDTA

group group p value

(Mean ± SD) (Mean ± SD)

Apical 3.6(0.4898) 3.3(0.4582) 0.1074
 Middle 3.2(0.6) 2.6(0.4898) 0.0192*
Coronal 2.6(0.489) 2.5(0.535) 0.3445
#
Mann Whitney Test, *Statistically significant

Table 12: Mean smear layer score in Hyflex - Qmix and WaveOne Gold - Qmix group.

WaveOne Gold -
Hyflex – Qmix group
Qmix group p value
(Mean ± SD)
(Mean ± SD)
Apical 2.9(0.3) 2.6(0.48) 0.1271
Middle 2.6(0.489) 1.8(0.4) 0.0018*
Coronal 2.1(0.3) 1.3(0.45) 0.0006*
# *
Mann Whitney Test, Statistically significant

DISCUSSION

The Endodontic therapy encompasses treatment of diseased coronal and radicular pulp, such that it

retains natural tooth in its form, function and aesthetics. The success of Endodontics depends on

proper cleaning and shaping followed by three dimensional obturation. Chemo-mechanical

preparation of root canal is done to get a bacterial free environment. 53

There are various types of hand and rotary driven instruments used for root canal treatment . These

instruments when used produces smear layer which is composed of organic and inorganic

substances, odontoblastic processes, microorganisms and necrotic material. To gain successful

clinical results in an endodontic therapy the smear layer should be efficiently removed.

The use of rotary nickel-titanium instruments in endodontics brought significant contributions to

clinical practice in terms of safety, speed, cleanliness and shaping of root canals. The Rotary files
have been subjected to constant changes in their form of metallurgy, design and the manner in

which these instruments are driven i.e rotary/reciprocation. 21

Additionally, a file is categorized as to whether it has a centered or offset mass of rotation, works

with a rotary or reciprocating motion, and in the instance of reciprocation, whether the clockwise

(CW) and counterclockwise (CCW), angles are equal or unequal. 12

This study evaluated the amount of smear layer removal produced by two type of single file system

i.e rotary Hyflex EDM and reciprocating Wave One Gold file system.

Rotary instrumentation has the enhanced ability to collect and remove debris from the canal system.

Advantages of alternating Niti instruments over continuous rotation are as follows: 1.It reduces

torsional stress by binding the instrument, to the root canal dentin walls less frequently. 2.It also

decreases the number of cycles thereby less flexural stress on the instrument. 3.Even the risk of

instrument fracture is reduced. Burklein et al compared the conventional rotating action instruments

with the instruments functioning in reciprocating motion. Reciprocating instruments produced less

residual debris when compared with other Rotary instruments. 24

In general, continuous rotation requires less inward pressure and it needs to improve on augering

debris out of a canal, when compared to a reciprocation method that utilizes equal bidirectional

angles of reciprocation. WaveOne Gold file is a newly designed file with semi-active guiding tip,

which enables the file to more readily to follow and safely progress along manually reproduced and

secured canals.12

Another entity to achieve good chemico-mechanical preparation is done by the use of irrigants.

Irrigation has a central role in endodontic treatment. During and after instrumentation, the irrigants

facilitate a flushing mechanism by removing microorganisms, tissue remnants, and dentin chips from

the root canal system.

The most widely used irrigant for root canal treatment is sodium hypochlorite. NaOCl acts as a

solvent of organic material and potent primary antimicrobial agent, while EDTA serves as the

inorganic solvent or chelating agent. A novel irrigating solution, QMix (DENTSPLY Tulsa Dental

Specialties, Tulsa, OK, USA) has been introduced to both remove smear layer and kill bacteria. This

irrigant has a proprietary formulation and method of preparation, and has been shown to remove

smear layer and kill recalcitrant bacteria, such as E. faecalis, in one application. 14,48 Qmix is a

proprietary blend which is composed of polyaminocarboxylic acid chelating agent, a bisbiguanide

antimicrobial agent, a surfactant and deionized water is an effective smear layer-remover and also

an powerful antimicrobial agent.

Furthermore, QMix does not interact with remnant NaOCl to generate a precipitate if used as

directed for the final rinse [Internal data on record with DENTSPLY Tulsa Dental Specialties, Tulsa,

OK, USA] and its ability to penetrate into patent, smear-plug free dentin to kill bacteria present has

been demonstrated using a novel model with potential significant clinical outcomes and

implications. Ethylenediamine tetra acetic acid (EDTA) is the most widely used irrigant for smear

layer removal.

QMiX is a novel endodontic irrigant for smear layer removal with added antimicrobial agents. It

contains EDTA, CHX and a detergent. QMiX removed smear layer as effectively as 17% EDTA based

on the number of fully opened dentinal tubules.

In the present study two single file system were evaluated for their effectiveness in removing smear

layer by using three different irrigants namely Naocl,EDTA and Qmix. Then the smear layer removal

ability was evaluated using, the criteria given by Hulssman et al and their scores were given

accordingly.

SEM studies are necessary when comparing the efficacy of removing the smear layer using various

instruments, irrigants and techniques. The coronal, middle and apical thirds of the root canals were
then viewed for evaluation. The representative areas for each group were photographed with a

scanning electron microscope (JSMt220A; JEol, tokyo, Japan) at ×1000 magnification. 48 The SEM

micrographs were evaluated for the presence of smear layer. The images are then coded and scored

by blinded evaluators with the help of qualitative or quantitative scales which had been described by

Hulsmann et al.28 In the present study (1997) Hulsmann et al criteria was used to score the smear

layer status. The evaluation is assessed by the scoring system of 60 teeth under the same conditions.

Data were analysed and their result of this study revealed that the distribution of smear layer scores

in the Hyflex – Naocl group (A1) were 4 (20%) , 5 (80%) in the apical third , in the middle third 4(50%)

, 5(50%) and 4(80%), 5(20%) in the coronal third of the root canal. The distribution of smear layer

scores in Hyflex – EDTA group (A2) were 3(70%),4(30%) in the apical third, in the middle third

2(10%), 3(90%) and 2(70%), 3(30%) in the coronal third of the root canal. The distribution of smear

layer in Hyflex – Qmix group (A3) were 2(10%), 3(90%) in the apical third, in the middle third 2(40%),

3(60%) and 2(90%) , 3(10%) in the coronal third of the root canal.

Whereas the distribution of smear layer scores in Waveone Gold – Naocl (B1) were 4(40%), 5(60%)

in the apical third, in the middle third 3(20%), 4(80%) and 3(60%), 4(40%) in the coronal third of the

root canal. The scores in WaveoneGold – EDTA group (B2) were 3(80%), 4(20%) in the apical third, in

the middle third 2(10%), 3(90%) and 2(70%), 3(30%) in the coronal third of the root canal. The

distribution of smear layer in Waveone Gold - Qmix group (B3) were 2(40%), 3(60%) in the apical

third, in the middle third 1(20%),2(80%) and 1(70%),2(30%) in the coronal third of the root canal.

While comparing the mean smear layer scores , the Hyflex EDM group had the highest smear layer

scores when compared with WaveoneGold group .

While comparing the mean smear layer scores with respect to the root canal sites in the root canal,

there was highest mean score in the apical third which is followed by the middle third and coronal

thirds of the root canal among both the groups. There was significant difference at the apical third

among all the groups.

While comparing the mean smear layer scores with respect to the irrigants used in the root canal

there was highest mean score in the Naocl group when compared with EDTA and Qmix group. There

was significant difference between the groups.

In the present study showed that WaveoneGold – Qmix group showed better results than other

groups. The use of single file system with reciprocating motion can both simplify the procedure and

remove the smear layer efficiently.

This study demonstrated that the use of reciprocating file system can remove the smear layer

efficiently for proper disinfection of the root canal.

CONCLUSION

Within the limitations of the present study the following conclusion were made as follows:

1.WaveoneGold group has better smear layer removal ability than Hyflex EDM group.

2.Qmix group showed lesser score, where smear layer removal is better than the Naocl and EDTA

group.

In all the groups there was increased smear layer removal at the coronal and middle third when

compared to the apical third of the root canal.