ORIGINAL RESEARCH ARTICLE

 

Analysis of cleaning, sterilization, storage process and frequency of endodontic instrument replacement of endodontists from the city of Caxias do Sul/RS

 

 

Suélen Fernanda Lunelli ^I; Tiago André Fontoura de Melo ^I; Caroline Berwanger Cord ^I

 

^I Dental School, College of Serra Gaúcha – Caxias do Sul – RS – Brazil

 

Correspondence

 

 

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ABSTRACT

Introduction: The maintenance of the aseptic chain associated with the knowledge and mastery of technique by the Endodontists are key factors for the success of endodontic treatment. Objective: This study aimed to evaluate, through a questionnaire, the care and cleaning, sterilization and storage methods of endodontic instruments, and the time of material disposal by endodontists from city of Caxias do Sul/ RS. Material and methods: Thirty-two endodontists participated in the study. The professionals answered a questionnaire with eight questions regarding biosecurity methods that they applied in their offices. Results: The cleaning process most adopted by most professionals was the use of brush associated or not with ultrasound. The disinfecting agent of choice by most respondents was the enzymatic detergent. All professionals performing the sterilization process by autoclave. Concerning to the disposal of manual endodontic instruments, fifteen participants reported to control the presence of twist or fracture and sixteen by the number of uses. For the rotary and reciprocating systems, most endodontists controlled the instrument replacement by the number of uses; with mean age of five uses for rotatory instruments. For the reciprocating system, different responses regarding the number of uses were reported. Conclusion: This study showed that the endodontists from Caxias do Sul/RS followed a satisfactory protocol for cleaning and sterilization of endodontic instruments. However, for the replacement of rotatory and reciprocating instruments, it was found that most professionals did not follow the manufacturers' recommendation.

Keywords: Endodontics; disinfection; sterilization; health knowledge, attitudes, practice.

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Introduction

The dentist is daily exposed during practice to various forms of contamination by pathogenic biological agents present in oral fluids such as blood and saliva ⁴. Thus, if previous biosecurity measures are not taken, the dentists are at risk of acquiring infectious diseases and enabling the occurrence of a cycle of cross-infection inside and outside the workplace ². In addition, the success of the treatment to be performed will not be based only and exclusively on the correct diagnosis, planning and technical implementation, but also on preserving and maintaining aseptic chain ⁸. That is, all aseptic care during treatment is essential to not only avoid the risk of infections, but also to achieve the objective of the proposed therapy ⁷.

The literature ^1,9,14,15,17 lacks consensus on both the technique/method more efficient and effective for cleaning of endodontic instruments and the right time to dispose them.

The re-use of instruments is a reality for the Endodontists because of financial issues for their replacement. However, to enable the reuse of endodontic instruments, it is essential to take some care, for example, in the process of cleaning, not to impair the sterilization process and jeopardize the treatment success ^11,16. In addition, to control the number of uses of the endodontic instruments is critical to use the qualities of the full material cut during the preparation and prevent the fracture of the material inside the canal due to negligence. Today, with the advent of the single-use mechanized systems, this issue of periodicity of use tends to be better controlled ⁶.

This study aimed to evaluate, through questionnaire, the care and cleaning, sterilization and storage methods of the endodontic instruments, and the time of material disposal, by the Endodontists from Caxias do Sul (RS).

 

Material and methods

This study was approved by the Research Ethics Committee under number #1.235.515. This quantitative research was conducted through a questionnaire answered by 32 Endodontists of the city of Caxias do Sul (RS). The Endodontists should be Specialist with certification recognized by the Brazilian Federal Council of Dentistry.

Initially, the dentists were instructed about the study objective to know the importance and the relevance of the answers of the questionnaire, to evaluate the knowledge of dentists on the care and biosecurity methods taken.

The questionnaire (table I) was directly applied by one of the researchers of the study, together with the obtainment of the signatures of the of Free and Clarified Consent Form. The dentist confidentiality was assured by numbering the questionnaires from 1 to 32. Thus, the name of the professionals would not be identified and they would not have the information disclosed and/or questioned.

 

 

 

The professionals were advised to mark only one answer per question, not being allowed to consult scientific literature on the subject. After data collection, these were tabulated and analyzed.

For the analysis of the data, descriptive analysis was performed with the value of the number of the answers to questions and the comparative percentage value between the alternatives marked on each of the questions.

 

Results

Based on the data obtained, it could be verified that the Endodontists time of graduation were equally distributed. Half of the professionals (16/32) were graduated for less than 10 years in the specialty, while the other half has been graduated for more than 10 years.

All Endodontists used autoclave for the sterilization of the endodontic instruments. There is diversity of responses regarding to cleaning/disinfection and method of storage. Most professionals made the cleaning of endodontic instruments using brush associated or not with ultrasound, and used some detergent, either conventional or enzymatic during the cleaning process. In terms of storage, the most used method was keeping the endodontic instruments wrapped in a gauze into a sterilization package (Table II).

 

 

 

With respect to the disposal and replacement of instruments, there was a diversity of responses according to the type of instrumental referred to: manual, rotational, or reciprocating. As regards to manual instruments, only one respondent reported to control the number of uses, discarding the material after the 10th use. The other respondents disposed the instruments only after deformation or fracture in the active part of the material.

On the other hand, with respect to the rotational instruments, the dentists demonstrated greater care at the right time for disposing the instrumental. Eighteen Endodontists reported that they control the number of uses. The mean time to dispose the material reported was after 5th use.

For the instruments of the reciprocating system, although 15 Endodontists interviewed did not report using this system, 10 professionals stated they controlled the moment of disposal according to the number of uses. However, there was different responses regarding the number of uses before disposal of the instrument.

The criteria adopted for the disposal of instruments and the number of uses of each instrument prior to disposal are expressed in Table III and graph 1, respectively.

 

 

 

 

 

Discussion

Considering the importance of the prevention of the risk of infection in dental office, as well as the searching to achieve success in the Endodontic treatment, basic biosecurity measures, such as proper cleansing of the instruments, sterilization and the subsequent replacement, should always be taken to maintain aseptic chain during the service.

The cleaning method adopted by professionals was one of the first questions made in the study. We observed that the use of a brush associated or not to the use of ultrasound was the most employed resource. It is already known, according to the literature ⁸, that there is no standardized technique to make the complete removal of debris present in the active part of the endodontic instruments, which can be done manually, with the use of ultrasound or association of both ¹².

Guandalini et al. ⁵ compared four different techniques of cleaning of endodontic instruments, namely: enzymatic cleaner + cleaning brush; ultrasound + enzymatic cleaner; ultrasound + water and gauze with alcohol. The results showed that all the techniques tested were efficient in removing debris except the gauze with alcohol, which proved to be ineffective. In the present study only 3.1% (1/32) of the respondents reported the use of gauze with alcohol to perform the clean process of the material.

In addition to the cleaning, the method adopted for sterilization of the instruments is very important. All professionals reported the use of autoclave for the completion of this process. This somehow meets the statements obtained in the studies of Raju et al. ¹³ and Guandalini et al. ⁵. According to these studies, the method of sterilization using autoclave proved to be 100% effective in microbial eradication power.

With respect to the time of disposal of the manual endodontic instruments, the preference for large part of Endodontists (18/32) was to control the replacement of rotational instruments by the number of uses, an average of 5 uses; none professional used the instruments only once. For the reciprocating system, 10 of the 32 respondents also controlled by number the uses, but there was a greater diversity in the disposal of the material regarding the use. These results showed that most of the respondents did not follow the recommendation of the manufacturers, which was the single use for both rotational and reciprocating instruments. The single use of the endodontic instruments avoids the risk of cross-infection during clinical practice, besides enabling the implementation of a safer treatment, such as the maintenance of some properties of materials, as mechanical strength and ability to cut ³. Such a result is worrying, because in case of the fracture of an instrument inside the root canal during the treatment, the dentist is both conniving and negligent with the accident.

However, some studies, such as Park et al. ¹⁰, suggest conducting more experiments to assess the possibility of not following the recommendation of the manufacturers and reuse the rotational and reciprocating instruments. In the same study, the authors observed that the rotational and reciprocating instruments can be reused safely at most in 5 different canals. However, these canals should not show any sharp curvature and other anatomical characteristics that make the procedure difficult, which may undermine and jeopardize the metallic structure and function of endodontic instruments.

For manual instruments, most Endodontists controls the material disposal by the presence of twisting or fracture of the active part. The stainless-steel alloy used in the manufacture of most manual instruments enables the dentist to have this control. Deformations, when present in the instruments, can be easily identified by direct vision. In clinical practice, the disposal of stainless steel manual instruments of lower size (#06, #08, #10, and #15) is more frequently than those of larger sizes, because of the smaller amount of metal mass, which causes greater loading and torsion during the mechanical-chemical preparation.

 

Conclusion

According to the obtained results, it was found that Endodontists from Caxias do Sul (RS) are following a protocol suitable for cleaning and sterilization. However, for the replacement of rotatory and reciprocating instruments, most of the respondents did not followed the manufacturers' recommendations.

 

References

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Corresponding author:
Caroline Berwanger
Cord Curso de Odontologia
Faculdade da Serra Gaúcha
Rua Os Dezoito do Forte, 2366
São Pelegrino
CEP 95020-472
Caxias do Sul – Rio Grande do Sul – Brasil
E-mail: carolineberwanger@yahoo.com.br

 

 

Received for publication: July 23, 2016
Accepted for publication: January 24, 2017