Dentistry Section DOI : 10.7860/JCDR/2017/23936.9852
Year : 2017 | Month : May | Volume : 11 | Issue : 5 Page : ZC29 - ZC35

A Survey on Nickel Titanium Rotary Instruments and their Usage Techniques by Endodontists in India

Thimmanagowda N Patil1, Prahlad A Saraf2, Raghavendra Penukonda3, Sneha S Vanaki4, Laxmikant Kamatagi5

1 Postgraduate Student, Department of Conservative Dentistry and Endodontics, P.M.N.M. Dental College and Hospital, Bagalkot, Karnataka, India.
2 Reader, Department of Conservative Dentistry and Endodontics, P.M.N.M. Dental College and Hospital, Bagalkot, Karnataka, India.
3 Postgraduate Student, Department of Conservative Dentistry and Endodontics, P.M.N.M. Dental College and Hospital, Bagalkot, Karnataka, India.
4 Senior Lecturer, Department of Conservative Dentistry and Endodontics, P.M.N.M. Dental College and Hospital, Bagalkot, Karnataka, India.
5 Reader, Department of Conservative Dentistry and Endodontics, P.M.N.M. Dental College and Hospital, Bagalkot, Karnataka, India.


NAME, ADDRESS, E-MAIL ID OF THE CORRESPONDING AUTHOR: Dr. Thimmanagowda N Patil, Room No. 03, Department of Conservative Dentistry and Endodontics, P.M.N.M. Dental College and Hospital, Bagalkot-587101, Karnataka, India.
E-mail: dr.tnpatil@yahoo.in
Abstract

Introduction

The preference and usage of nickel titanium rotary instruments varies from individual to individual based on their technique, experience with the rotary systems and the clinical situation. Very limited information is available to explain the adoption of changing concepts with respect to nickel titanium rotary instruments pertaining to the endodontists in India.

Aim

The aim of this study was to conduct a questionnaire survey to acquire the knowledge concerning different NiTi rotary instruments and their usage techniques by endodontists in India.

Materials and Methods

A Survey questionnaire was designed which consisted of 32 questions regarding designation, demographics, experience with rotary instruments, usage of different file systems, usage techniques, frequency of reuse, occurrence of file fracture, reasons and their management was distributed by hand in the national postgraduate convention and also disseminated via electronic medium to 400 and 600 endodontists respectively. Information was collected from each individual to gain insight into the experiences and beliefs of endodontists concerning the new endodontic technology of rotary NiTi instrumentation based on their clinical experience with the rotary systems. The questions were designed to ascertain the problems, patterns of use and to identify areas of perceived or potential concern regarding the rotary instruments and the data acquired was statistically evaluated using Fisher’s-exact test and the Chi-Square test.

Results

Overall 63.8% (638) endodontists responded. ProTaper was one of the most commonly used file system followed by M two and ProTaper Next. There was a significant co relation between the years of experience and the file re use frequency, preparation technique, file separation, management of file separation.

Conclusion

A large number of Endodontists prefer to reuse the rotary NiTi instruments. As there was an increase in the experience, the incidence of file separation reduced with increasing number of re use frequency and with experience, the management of separated file was better.

Introduction

Root canal treatment is one of the most technically challenging procedures in dentistry and the success depends on the diagnostic acumen, instruments used and the technologies adopted. The adoption of endodontic nickel titanium rotary technology by endodontists in India has increased two folds in the last two decades. Although, all endodontists use rotary technology there is a significant disparity in the different systems used, frequency of the use and the methods of use [1]. A survey was conducted to understand the scenario of rotary NiTi usage by endodontists in India.

Endodontic treatment encompasses procedures that are designed to maintain the health of all or part of the pulp. When the pulp is diseased or injured, treatment is aimed at preserving normal periradicular tissues. When pulpal diseases have spread to the periradicular tissues treatment is aimed at restoring them to health. This is usually achieved by root canal treatment [2].

Cleaning and shaping of the root canal system is one of the main goals in endodontics which can be carried out using different systems and techniques [3]. Traditionally, stainless steel used in the manufacturing of the hand instruments for root canal shaping lack flexibility with increasing sizes and can lead to procedural errors [4] resulting in a decreased success rate for endodontic treatment [5].

In 1988, root canal instruments manufactured from nickel-titanium (NiTi) alloy were introduced to overcome the rigidity of stainless steel [6]. NiTi is one of several shape memory alloys, but this particular alloy of two metals has the most important particular applications in medicine and dentistry due to its biocompatibility and corrosion resistance [7]. NiTi alloy was discovered by Buehler HM et al., and named Nitinol which stands for nickel, titanium, Naval ordinance Laboratory [8]. In endodontics, NiTi was initially reported for use by Walia HM et al., [9].

Nickel titanium instruments have the advantage of instrumentation with reduced procedural errors. They are two to three times more flexible and have superior resistance to torsional fracture as compared to stainless steel [10]. Various NiTi rotary systems are being constantly released. Continuous improvements have been made to the instruments design with the implementation in the hope of achieving better and safe shaping with reduced risk of procedural accidents, such as transportation or file separation [6].

Furthermore, there is a perception among clinicians and researchers that the number of use of an instrument may be an important factor in the defect rate [11].

The introduction and development of nickel-titanium rotary instruments is undoubtedly a quantum leap for the field of endodontics. Endodontists who have gained some experience in the use of nickel-titanium rotary instruments will confirm that each file system has its own special characteristics pertaining to advantages and disadvantages and the particular rules for its usage are to be followed [12].

Very limited information is available regarding the adoption of nickel titanium rotary instruments and instrumentation by endodontists in India.

Thus, the aim of this study was to conduct a questionnaire survey to acquire the knowledge concerning different NiTi rotary instruments and their usage techniques by endodontists in India.

Materials and Methods

The study was conducted in the Department of Conservative Dentistry and Endodontics, PMNM. Dental College and Hospital, Bagalkot, Karnataka, India.

The questionnaire was designed and the validity was assessed by distributing to eight experienced endodontists with a minimum experience of five years after postgraduation. The questionnaire designed was validated for relevance of questions particular to the topic of the survey (Face validity) and also for the reliability of the options provided (Content validity). A pilot survey was conducted on 25 endodontists to assess the reliability and internal consistency of the questionnaire which revealed that the survey was reliable with the Cronbach’s alpha internal consistency score of 0.8. The data obtained from the pilot study was used to determine the sample size, using the formula N=4PQ/D2 [13] (where N stands for sample size, P stands for highest prevalence, Q =100-P and D stands for acceptable error or lowest prevalence) thus sample size obtained yielding the average sample size of 519.6. Then the sample size obtained was rounded off to nearest hundred and the sample size for the survey to be conducted for a minimum of 500 endodontists to ascertain the results was determined. Thus 1000 endodontists were given the questionnaire in a systemic random sampling manner. Questionnaire was distributed to specialists of 29 different states to represent the entire Indian population of endodontists.

A survey questionnaire was disseminated via two methods; electronic media and on site to 1000 endodontists. The on-site questionnaire was distributed to 400 endodontists who attended 17th IACDE-IES national post graduate convention held at Bhopal in April 2016. Questionnaire was also sent through electronic media to 600 endodontists in India. The repetition of the endodontists was avoided by the demographic data collection and subsequent elimination of the particular institution. The mailing address was gathered from the souvenirs of the convention and through personnel contacts. The survey consisted of 32 questions, many of which had multiple options and every question was indicated as mandatory. A questionnaire was used for collecting information from each individual regarding designation, demographics, experience with rotary instruments, usage of file systems and methods, frequency of reuse, occurrence of file fracture during canal preparation, reasons for file fracture, management of fractured files and usage frequency of reciprocating and self adjusting file system with advantages and disadvantages.

Questions were constructed by using check boxes, multiple options and with the option for free text. Selection of more than one answer was allowed. The questions were based on information gathered from recent reviews and textbooks on root canal preparations.

The data was collected from endodontists by using the online interface during a four month period and on site questionnaire distributed were collected within a time period of two days. Questionnaire distributed through electronic media was formatted to allow single or multiple responses on the basis of the focus of the question. To ensure all questions were completed, an alert was delivered if one or more questions were left unanswered. To facilitate collecting unbiased data, respondent’s personnel information regarding their name, age or sex was not included in the questionnaire. The survey was completely anonymous and identification of the participant was not linked to the individual responses.

Statistical Analysis

Responses received on site and through electronic media were formatted to allow analysis by using the SPSS version 19.0 (IBM Corp, Armonk, NY, USA) with Fisher’s-Exact test and the Chi-Square test. Chi-Square test was applied to determine whether there was a significant association between the two categorical variables from a single population of endodontists. Percentages were calculated based on the number of responses or respondents to each question. The correlation between the preparation technique and the file separation, experience with frequency of file separation, experience with management of file separation, experience with repeated reuse were assessed.

Results

This study achieved an overall response rate of 63.8%. From 638 respondents of the current survey, 135 (21.2%) were academician and clinician, 64 (10%) were only clinicians and 439 (68.8%) were post graduate students. The experience using rotary file system for more than five years was 28.1%, from one year to five years was 35.9%, six months to one year and less than six months was 22.3% and 13.8% respectively.

The data from the responses received was categorized accordingly with the data regarding the use of various rotary files system [Table/Fig-1], data regarding the rotary usage and preparation techniques [Table/Fig-2], data regarding initial enlargement, coronal preparation and usage frequency of reciprocating and self adjusting file system [Table/Fig-3], data regarding the re use of rotary file systems [Table/Fig-4], data regarding file separation, reason for file separation and the management of separated file [Table/Fig-5,6 and 7], data regarding the advantages and disadvantages of rotary, reciprocating and self adjusting file system [Table/Fig-8,9].

Data regarding various rotary file systems used.

FrequencyPercent
Which file system are you using nowProtaper next26741.8
Protaper55086.2
M two36657.4
Race6510.2
Revo S11518.0
Neolix neo Ni Ti12619.7
One shape9214.4
Hyflex8413.2
K37411.6
Flexicon60.9
Komet F360101.6
V taper477.4
Reciproc172.7
Chinese10.2
Hero shaper60.9
Heroshaper twisted10.2
Light speed30.5
Profile system10.2
SAF10.2
Silk10.2
TF10.2
Twisted files20.3
Wave one152.4
Wave One Gold10.2

Data regarding rotary techniques.

FrequencyPercent
Why do you use rotary file systemFollows the canal anatomy better37859.2
Better cleaning efficiency36356.9
Time factor40563.5
Fracture resistance609.4
Ease of use42466.5
Cost factor29646.4
Mostly used10.2
Waveone has less screwing effect in canal. Hence less file breakage10.2
Wizard navigator10.2
FrequencyPercent
What is your preparation techniqueCrown down technique34654.2
Hybrid preparation technique26441.4
Sequential manner274.2
Step back10.2
Total638100.0
FrequencyPercent
Do you prefer rotary instrumentation in upper anterior teethNo48676.2
Yes15223.8
Total638100.0
FrequencyPercent
Do you use glide path rotary filesDepends on the canal274.2
No36056.4
Some times639.9
Yes18829.5
Total638100.0

Data regarding intial enlargement, coronal preparation and usage frequency of reciprocating and self adjusting file system.

FrequencyPercent
Do you initially enlarge the canal before rotary instrumentation with K file15 no. K file17227.0
20 no. K file35956.3
25 no. K file467.2
Depends on the canal619.6
Total638100.0
FrequencyPercent
Do you use coronal enlarging fileGates Glidden or large number K file416.4
GG drills10.2
No12319.3
Orifice opener10.2
Orifice openers or Sx file10.2
Protaper Sx10.2
Sometimes when orifices are apart10.2
Sx10.2
Yes46873.4
Total638100.0
FrequencyPercent
Have you used reciprocating file systemNo54485.3
Yes9414.7
Total638100.0
FrequencyPercent
Have you used self adjusting file systemNo57990.8
Yes599.2
Total638100.0

Data regarding re use of rotary file system.

FrequencyPercent
How many times do you re use your rotary file system2 uses172.7
3-5 uses18529.0
5-10 uses40863.9
More than 10 uses223.4
Single use60.9
Total638100.0
FrequencyPercent
When do you discard rotary file systemAfter decrease in the cutting efficiency17126.8
After repeated re use35255.2
After the file separation7611.9
After using in curved canal396.1
Total638100.0
FrequencyPercent
How do you remember the number of times the files are usedMarking on files36657.4
Recording on paper19530.6
Removal of petals416.4
Others365.6
Total638100.0

Data regarding file separation.

FrequencyPercent
What is the estimated frequency of file separation in the root canal (after how many cases)After 181.3
After 10507.8
After 2111.7
After 371.1
After 4253.9
After 58913.9
After 614122.1
After 7335.2
After 822735.6
After 9193.0
After more than 10284.4
Total638100.0
FrequencyPercent
What is the estimated frequency of file separation ’ in root canalIn less than a week142.2
Less than five times a year19831.0
Once in 15 days8413.2
Once in a month23937.5
Once in a week335.2
Rare7011.0
Total638100.0
FrequencyPercent
Do you think that the separation of file has decreased with your increasing experience on rotary file systemNo436.7
Yes59593.3
Total638100.0

Data regarding file separation.

FrequencyPercent
Where does the majority of the file separation occursLower anteriors30.5
Upper premolars buccal root30.5
Upper premolars palatal root40.6
Upper molars Mesiobuccal canal19931.2
Upper molars distobuccal canal243.8
Lower molars Mesiobuccal canal37158.2
Lower molars Mesio lingual canal46472.7
Lower molars distal canal60.9
Lower premolars10.2
Upper anteriors10.2
FrequencyPercent
Where does the separation occurs most commonlyApical one third56388.2
Middle one third7511.8
Total638100.0
FrequencyPercent
Do you think the incidence of file separation decreases withHand piece with speed and torque control61696.6
Hand piece without speed and torque control223.4
Total638100.0
FrequencyPercent
Does the irrigation protocol decreases the file separationIrrigation play a minor role. I believe it’s always a good glide path and extended duration of using hand files decrease the fractures.10.2
EDTA to be used properly10.2
No589.1
To some extent10.2
Yes57790.4
Total638100.0

Data regarding reason for file separation and management of file separation.

FrequencyPercent
What may be the common reason for file separation in the canalExcessive pressure on file50779.5
Incorrect insertion angle of the file19831.0
Non constant speed of rotation528.2
High R P M477.4
Infrequent irrigation32851.4
Calcified canal13521.2
Over usage37358.5
Inappropriate torque settings26541.5
Type of file233.6
Complex root canal anatomy18028.2
Incorrect file sequence34654.2
File design10.2
Unknown40.6
FrequencyPercent
How do you manage separated instrumentsRetrieve the instrument26341.2
Bypass the separated instrument51881.2
Obturation over the separated instrument35155.0
Depends on preoperative infection status and level of fracture of instruments10.2
Depends the place of seperation and irrigation protocol10.2
Refer10.2
Retrieve if in coronal otherwise bypass.. If it doesn’t happen then obturate if patient is symptom free.10.2
Variable for each case10.2

Advantages and disadvantages of rotary and reciprocating file systems.

FrequencyPercent
What is the advantage of using rotary file systemDecreased procedural errors30648.0
Time saving53984.5
Ease of use41264.6
Maintaining the canal anatomy and curvature better29946.9
Maintains working length497.7
Easier canal obturation41565.0
Patient factor487.5
At times being an endodontic. Rotary is expected10.2
FrequencyPercent
What are the disadvantages of using rotary file systemLedging of the canal9414.7
Transportation7311.4
Strip perforation365.6
Straightening of the canal6510.2
Binding of the file9915.5
File separation53383.5
Excessive dentin removal45070.5
Expensive10.2
FrequencyPercent
What are the advantages of using reciprocating file systemReciprocating motion28745.0
Time factor7511.8
Reduced incidence of file separation49477.4
OthersNoNo advantage not sureNot used.111.8
 
FrequencyPercent
What is the disadvantages or why have you not used reciprocating file systemCost factor28745.0
Availability of files609.4
Need for reciprocating hand piece52181.7
None60.9

Advantages and disadvantages of self adjusting file system.

FrequencyPercent
What are the advantages of using self adjusting file systemContinuous irrigation42166.0
Time factor7411.6
Reduced incidence of file separation47274.0
   
Better cleaning and shaping10.2
canal anatomy is preserved10.2
Cost10.2
Doesn’t change the original anatomy. Suitable for non circular canals10.2
Maintains Canal anatomy10.2
No advantage, rotary is equally better10.2
not sure40.6
Not used71.1
reduce dentin removal10.2
FrequencyPercent
What are the disadvantages or why have you not used self adjusting file systemCost factor31449.2
Availability of files629.7
Need for specialized hand piece50378.8
Don’t know30.5
Need for GlidePath with rotary files10.2
Not used20.3
SAF does shape and enlarge the canal … It only helps in cleaning the canal10.2
Used10.2

There was a significant correlation between the initial enlargement with K files and the frequency of re using the file system. But when the initial enlargement was upto 25 K file showed varied correlation with least number of respondents favouring enlargement till 25 K file. The correlation between the preparation technique and re using the file systems revealed hybrid preparation technique was more efficient. With the increasing experience on the rotary file system the frequency of re using the file system increased and as well the management of separated file system [Table/Fig-10].

Co-relation data.

Co-relation between initial enlargement and file re use, Chi square value(df)= 10.64(6), p=0.10(NS)
Initial enlargementRe-usesTotal
1 - 56 - 10more than 10
15 no. K file45 (26.2%)120 (69.8%)7 (4.1%)172
20 no. K file69 (19.2%)276 (76.9%)14 (3.9%)359
25 no. K file16 (34.8%)27 (58.7%)3 (6.5%)46
Depends on the canal10 (16.4%)47 (77.0%)4 (6.6%)61
Total140 (21.9%)470 (73.7%)28 (4.4%)638(100.0%)
Co-relation between biomechanical preparation technique and file separation, Fisher’s exact test = 0.01*
Preparation techniqueFile separationTotal
After 1 - 5After 6 - 10After more than 10
Crown down technique86 (24.9%)246 (71.1%)14 (4.0%)346
Hybrid preparation technique46 (17.4%)208 (78.8%)10 (3.8%)264
Sequential manner7 (25.9%)16 (59.3%)4 (14.8%)27
Step back1 (100.0%)001
Total140 (21.9%)470 (73.7%)28 (4.4%)638 (100.0%)
Co-relation between years of clinical experience with rotary files and file separation, Chi square value(df)= 29.34(6), p<0.001*
YearsFile separationTotal
After 1 - 5 timesAfter 6 - 10 timesAfter more than 10 times
1 year to 5 years36 (15.7%)181 (79.0%)12 (5.2%)229
6 months to 1 year44 (31.0%)89 (62.7%)9 (6.3%)142
Less than 6 months31 (35.2%)54 (61.4%)3 (3.4%)88
More than 5 years29 (16.2%)146 (81.6%)4 (2.2%)179
Total140 (21.9%)470 (73.7%)28 (4.4%)638
Co-relation between years of clinical experience with rotary files and method of management of separated instrument
YearsTotalChi square test
1 year to 5 years6 months to 1 yearLess than 6 monthsMore than 5 yearsChi square valuep-value
Retrieve the instrument84 (36.7%)33 (23.2%)24 (27.3%)122 (68.2%)263 (41.2%)81.56<0.001*
Bypass the separated instrument182 (79.5%)109 (76.8%)67 (76.1%)160 (89.4%)518 (81.2%)11.610.009*
Obturation over the separated instrument141 (61.6%)86 (60.6%)33 (37.5%)91 (50.8%)351 (55.0%)17.92<0.001*
Others2 (0.8%)1 (0.7%)02 1.2%)5 (0.8%)--

p<0.05 statistically significant; p>0.05 Non significant, NS

Fishers Exact test and Chi square test used.


Discussion

This survey was conducted with an intention to collect data from Indian endodontists regarding the usage of different NiTi rotary instruments and their usage techniques. Although such survey data are available from other countries such as Australia [14], the UK [2], Denmark [15], the United States [16], Tehran [3], French dental schools [17] and Flemish [18], Wales [1,19, 20] comparatively little is known about the different NiTi rotary instruments usage and their techniques in India.

The distribution of the survey forms by hand and via electronic media was done. Collection of data via electronic media offered a unique set of strength as this method facilitated access to large groups, improved response percentages by offering the ability to send reminder messages, calls and guaranteed completion of each question by using an incomplete error message for unanswered questions during the submission process [16].

This study had an overall response rate of 63.8%, which was acceptable for dental surveys (50-70%) [6]. Purpose of this questionnaire survey was to gain insight into the experiences and beliefs of endodontists concerning the new endodontic technology of rotary NiTi instrumentation as the successful introduction of new NiTi rotary technology into daily clinical practice would require not only effective products, but also the appropriate and adequate data with quality information for the usefulness of the practitioners [1,7,19]. The questions were designed to ascertain the problems, patterns of use and to identify areas of perceived or potential concern. Furthermore, it was intended that the information so obtained would allow a better understanding of the needs within the Indian endodontic community.

Experienced operators combine instruments from different file systems and use different instrumentation techniques to achieve best biomechanical cleaning and shaping results, resulting in the fewest procedural errors [6].

It is recommended that NiTi rotary instruments be discarded after a single use. A single use is ideal for reducing the risk of file separation; however, the high operating cost of NiTi files has forced clinicians to reuse them. There are so many factors governing the safe re use of NiTi rotary file systems which mainly depends on the number of re uses, preparation technique employed, glide path preparation prior to rotary instrumentation and initial apical preparation and enlargement of the canal using hand K files, sufficient orifice enlargement or the coronal preparation and the use of adequate irrigant and lubrication with the file system [6].

The preparation technique was associated with the frequency of file separation. Operators who use the sequential total length technique tended to experience file fracture more than crown down and hybrid preparation technique. The crown down technique has been used for more effective cleaning and shaping. It minimizes coronal interference, decreases the torque load of each instrument and reduces procedural errors. The hybrid technique does not deviate from the principles of the crown down preparation [6].

Prior to use of any NiTi rotary instruments, a passive glide path for these instruments upto ISO size 20 with stainless steel K hand files is essential so that the fragile tips of small sized NiTi rotary instruments can follow the path created without exploring the canal or cutting. Even light pressure or a small amount of torque with inadequate glide path would otherwise fracture these instrument tips [12]. So, it is recommended that the use of stainless steel hand files to prepare the apical 1/3rd before introducing rotary files, to reduce the incidence of file breakage [21].

The frequency of reusing NiTi files differed according to experience. Experienced operators had a strong tendency of reusing the files 6-10 times. This was due to the experience based opinion that a file can be safely re used more. It seems that experienced operators do not rush through a procedure, so that it could decrease the chance of torsional failure [22,23].

Instrument fracture occurs during preparation of the root canal when the root canal still is rather narrower and not finally flared. The majority of the fractures had occurred in molars; the most frequently involved root canals were the mesial canals of mandibular molars followed by buccal canals of maxillary molars [24]. The responses obtained were comparatively similar with that of the PennEndo database study [10].

Instrument separation was 33.5 times more likely to occur in the apical one third versus the coronal one third of the tooth [10]. Similar responses were obtained according to the respondents of this survey.

Majority of the respondents agreed that the incidence of file separation decreases with the irrigation protocol and with hand piece having speed and torque control. The galenic form of a lubricant was the main factor to influence mechanical stresses on instruments. Aqueous solutions were superior to a gel type preparation. Furthermore, the addition of a chelating agent caused some further decrease in torque, torsional load, and force values. This effect occurred immediately [25].

The management of separated files is multifactorial, the removal of the fractured NiTi instruments is more influenced by such factors as the anatomy of tooth, degree of root canal curvature, and the location of fragment than the specific technique used [26]. There was an improvement in the management of the separated files with the increasing experience.

Although instrument breakage in some cases sharply increases the chance of case failure, it does not in general act as a particularly powerful influence toward case failure. The rather high success rate obtained in spite of instrument breakage suggests that instances a broken instrument does not have an adverse effect on the prognosis [27].

Root canal instruments should be examined before being introduced into a canal to make sure that the spiral twists are regularly aligned. If the blades are not spaced equally, it is an indication that the instrument has been strained and that the torque has caused the blades to become irregularly spaced. The spacing may be closer together or further apart than normal, depending on whether the instrument had been originally wound clockwise or counter-clockwise by the manufacturer. Instruments with irregularly spaced blades are likely to break. Instruments should also be examined as they are removed from the canal and are being cleaned on a cotton roll prior to sterilization. A quick glance is sufficient to determine whether the instrument has been under strain and should be discarded [28].

The study addressed to the various instruments and instrumentation technologies of rotary NiTi which will help in understanding the clinical implications which will provide a better platform for the endodontists to carefully select and eliminate different instrument systems and methods catering to the future prospects to the endodontists in India.

Limitation

The limitation of the survey was that the study did not include the questions regarding the advantages of hand over rotary systems, the time consumed by hand over rotary systems and the success rate of hand over rotary systems. It also did not include the questions regarding the sterilization technique adopted by the endodontists after each use of the file system.

Conclusion

Increased success rates of root canal treatment is still not a conclusive finding with the rotary instrumentation but there is evidence in the endodontic literature which proves that rotary instruments have several advantages over traditional hand filing techniques. The dissemination of the data to the various regions of India gave an insight regarding the usage of rotary NiTi instruments and techniques by endodontists in India.

The adoption of new endodontic technologies among endodontists in India has significantly contributed to the enhancement of the quality of endodontic treatment. The present survey provided the qualitative and quantitative information regarding the various aspects of rotary NiTi systems. Questionnaire based studies can serve as a useful tool in successful practice.

*p<0.05 statistically significant; p>0.05 Non significant, NSFishers Exact test and Chi square test used.

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