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Year : 2023  |  Volume : 13  |  Issue : 1  |  Page : 94-99

Dental health-care professionals' awareness and knowledge of sterilization and disinfection practices for new, unused endodontic files and gutta-percha in Jeddah, Saudi Arabia

1 Department of Endodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia
2 Department of General Dentistry, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia
3 Department of Oral Biology, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia
4 Department of Dental Public Health, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia
5 Department of Restorative Dentistry and Endodontics, College of Dentistry, Riyadh Elm University, Riyadh, Saudi Arabia

Date of Submission15-Oct-2022
Date of Decision29-Oct-2022
Date of Acceptance29-Oct-2022
Date of Web Publication11-Jan-2023

Correspondence Address:
Dr. Khalid Merdad
Department of Endodontics, Faculty of Dentistry, King Abdulaziz University, P. O. Box: 80209, Jeddah 21589
Saudi Arabia
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/sej.sej_176_22

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Introduction: The proper protocol for the sterilization of instruments is essential in dental practice; especially because some clinicians think that new files directly from the manufacturers are already sterile and can be used directly on patients without the standard sterilization. Therefore, the aim of this study is to analyze the dental levels of professionals and their auxiliary staffs concerning awareness, knowledge, attitudes, and behaviors about sterilizing endodontic instruments and gutta-percha.
Materials and Methods: This cross-sectional study was conducted in Jeddah, Saudi Arabia, using an online, randomly distributed survey for dental health-care practitioners. The survey questions were about the participants' demographics, knowledge, attitudes, and behaviors about sterilization techniques for endodontic files and gutta-percha. Data analysis consisted of simple descriptive statistics presented in frequency tables and percentages.
Results: Of the 197 dental health-care practitioners surveyed, the majority (84.7%) stated that they use files directly from the manufacturer's packages, while only 15.3% reported sterilizing the new endodontic files before using them with patients. As for gutta-percha, 23.4% of the participants answered that they disinfected it before obturation. About 60% of the participants were unaware that the sterilization's expiry date was printed on the endodontic file packages.
Conclusions: The results indicated that the majority of dental practitioners and students do not practice an effective sterilization protocol for endodontic files and gutta-percha. Based on these results, this study recommends that more education about sterilization protocols should be added to the infection control curriculum.

Keywords: Disinfection, endodontic files, gutta-percha, sterilization, survey

How to cite this article:
Merdad K, Alnaffaie M, Balbaid R, Nakity A, Alghamdi F, Sabbahi D, Al Nazhan S. Dental health-care professionals' awareness and knowledge of sterilization and disinfection practices for new, unused endodontic files and gutta-percha in Jeddah, Saudi Arabia. Saudi Endod J 2023;13:94-9

How to cite this URL:
Merdad K, Alnaffaie M, Balbaid R, Nakity A, Alghamdi F, Sabbahi D, Al Nazhan S. Dental health-care professionals' awareness and knowledge of sterilization and disinfection practices for new, unused endodontic files and gutta-percha in Jeddah, Saudi Arabia. Saudi Endod J [serial online] 2023 [cited 2023 Feb 3];13:94-9. Available from: https://www.saudiendodj.com/text.asp?2023/13/1/94/367515

  Introduction Top

In modern endodontic treatments, the primary goal is the eradication of microorganisms and their by-products from the root canal system before an obturation.[1],[2] Bacteria in instrumented, untreated canals may proliferate and approach the pretreatment quantities after 2–4 days, according to some researchers.[2] The microorganisms' persistence is the primary reason for intra- and extraradicular infections that resisted disinfected measures.[3] Microorganisms can invade the root canal system after caries, trauma, periodontal disease, iatrogenic operative procedures, and infected instruments.

For decades, the understanding of the pathobiology of root canal infections, such as microbial compositions, biofilm biology, and host responses to infections, was emphasized to develop clinically effective treatments and preventive therapies.[3] Sterilization of endodontic instruments is well known for decreasing the risk of infections and bacterial transmissions during treatments; therefore, strict infection control protocols and aseptic techniques for root canal systems are essential to successful treatment outcomes.[4],[5]

A typical root canal treatment involves chemomechanical debridement of the pulpal tissues using manual and engine-driven files, followed by obturation using gutta-percha cones and root canal cement sealers.[6] The sterility of new and unused endodontic files from different manufacturers was tested by two studies.[7],[8] The results showed that different manufacturers' endodontic files were biologically contaminated.[7],[8] For example, Zmener and Spielberg stated that some of the new and unused files were as unclean as the sample they examined that was covered with debris.[9]

Staffs used different methods for cleaning and disinfecting dental instruments to ensure optimal health results.[10] However, the current sterilization of endodontic instruments may not be correct among dental professionals in Jeddah. Although many studies have assessed the sterility of endodontic tools, there is still a gap in the evidence about the knowledge, attitudes, and behaviors of dental health-care providers regarding the sterilization of endodontic instruments in Saudi Arabia.

To our knowledge, this is the first study about sterilizing new and unused endodontic files and gutta-percha for evaluating dental professionals' knowledge and awareness of the current protocols for infection control.

The aim of this study is to assess dental health-care professionals' levels of knowledge, attitudes, and behavior regarding the sterilization of new and unused endodontic instruments.

  Materials and Methods Top

A descriptive, cross-sectional study was conducted with dental health-care professionals in Jeddah, Saudi Arabia. The study used a convenience sample that was randomly selected from five academic institutes, two public hospitals, and a private practice and included dental students, interns, general dentists, and endodontists. Sample size was calculated using an online calculator (www.raosoft.com) (Raosoft, Inc., Seattle, WA, USA). The sample size calculation was based on population size of 1500 and 95% confidence intervals with a margin of error of 7.5%, which yielded a sample size of 154 participants. Ethical approval (#309-11-21) was obtained from the Research and Ethics Committee at King Abdulaziz University, and all the participants gave their consent. Participants were interviewed using a structured questionnaire. Privacy was guaranteed, and the individual results remained confidential.

The survey questionnaire was developed by the authors and reviewed by three faculty members in the Department of Endodontics at the Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia. The questionnaire was constructed in English and was pretested on 25 persons (five persons in each group of five groups) including dental student group, intern group, general practitioner group, dental assistant group, postgraduate student group, and endodontist group who were not part of the study sample. The questionnaire consisted of 23 closed-end questions. Five questions were asked about the participants' sociodemographic data: gender, education, university (graduated from or currently studying at the faculty of dentistry), place of work, and the participants' teaching activities, if any. The other questions were targeted at the participants' knowledge of, and attitudes toward, sterilization and disinfection of new files and gutta-percha.

The questionnaire data were compiled and analyzed using IBM SPSS 25.0 (Chicago, Illinois, USA, 2016). Descriptive statistics summarized the data using frequency tables and percentages.

  Results Top

A total of 197 of 200 participants agreed to participate in the study, for a response rate of 98.5%. About 61% of the participants were female. The majority of the participants were dental students and interns, 46.7% and 31%, respectively. The rest were general practitioners, dental assistants, postgraduate students, and endodontists, 7.6%, 7.1%, 5.1%, and 2.5%, respectively.

Most participants (78.7%) thought that new and unused endodontic files were sterilized and ready to use, while the remaining 21.3% thought that they should be sterilized before being used.

In response to the question about sterilizing new packages of endodontic files, the majority of the participants (84.7%) stated that they used them soon after taking them out of the manufacturer's packaging, and the remaining 15.3% reported sterilizing the new and unused endodontic files before using them.

The assessment of the participants' knowledge and awareness about the infectivity of new endodontic files showed that 69% agreed that new files can transmit viral and bacterial infections. In contrast, the 31% disagreed about the files' infectivity. Similarly, 66% thought that infected endodontic instruments and materials can spread viral and bacterial infections and 34% did not.

As for the respondents' results regarding their knowledge of which method they thought is the best for cleaning endodontic files after using them, 29.4% chose an ultrasonic bath, followed by an alcohol swap and chemical solutions, 26.4% and 16.8%, respectively. About 15.3% did not know the best method for clean endodontic files after using them. The rest of the answers involved using napkins, cotton rolls, disinfectants, sodium hypochlorite (NaOCl), and chlorhexidine.

When asked about their actual postuse cleaning of the endodontic files, 59.4% stated that they did not clean the files because they thought that they were going to be sterilized, while 30.6% said that they cleaned them if they were grossly contaminated or they relied on a dental assistant to clean them. The remaining 10% stated that they discarded the file if it was contaminated.

An assessment of knowledge regarding the best method for sterilizing endodontic files revealed that respondents chose autoclave, dry heat, and glass bead sterilization (83.8%, 6.1%, and 1.5%, respectively). Only 8.6% stated that they did not know the best method.

An evaluation of the participants' practices for disinfecting gutta-percha cones revealed that 76.6% did not disinfect the cones before obturation, indicating that only 23.4% did. Those who disinfected the gutta-percha cones use different methods, including immersing them in 5.25% NaOCl for 1 min, wiping with an alcohol swap, or using dry heat sterilization.

More than half of the sample (57.4%) thought that successful endodontic treatment outcomes were related to using disinfected and sterile files and gutta-percha. About 11.1% did not believe in this relation, and 31.5% thought that the outcome depended on the specifics of each case. Regarding whether the respondents placed endodontic files and gutta-percha on a sterile surface in their practice, the majority (66%) stated that they do (34% did not).

An assessment of the participants' knowledge of the sterility status printed on the back of the new endodontic file packages revealed that 37.1% were unaware, 20.3% were aware and checked it, 20.8% forgot to check it most of the time, and 21.8% do not check it at all. As for the date of expiration, 60.9% did not know that sterilization had an expiry date, 24.4% were aware of it, but they do not check it, while only 14.7% checked it.

When asked if using only one file from a bag of sterile endodontic files affected the sterility of the other files, more than half of the participants (54.8%) believed that this does not affect the sterility of the unused files.

  Discussion Top

The infection prevention guidelines make it clear that using sterile instruments that touch blood is essential for preventing the spread of pathogens.[11] Endodontic treatments typically involve touching soft tissues and blood, if any; therefore, an aseptic technique is an essential part of the process.[12] Moreover, using sterile endodontic instruments prevents the spread of the microorganisms that are the major cause of a periapical pathology.[13]

The survey was completed by respondents from all of the academic institutes in Jeddah, Saudi Arabia. It was also distributed to general practitioners and endodontic specialists working in public and private practice in the city. Although the response rate was moderate, the sample selection process was intended to be as representative as possible of the dental professionals in Jeddah.

As discussed in the results section, the majority of the respondents did not disinfect new and unused endodontic files or gutta-percha and, instead, took them from each manufacturer's packaging. This major finding is a direct result of their limited knowledge regarding the sterility status of all new files. Most (74.0%) believed them to be sterile regardless of the packaging labels. Although 69.0% agreed that new endodontic files could transmit infections, they showed a negative attitude toward practicing correct infection control measures. Moreover, 84.5% indicated that they used endodontic files and sterilized them multiple times before discarding them. However, this usage could result in cross-infections without proper decontamination of the instruments.

Our findings are in line with a survey distributed in the United States to endodontists and general dentists in similar cohorts. That study showed that 61.0% of endodontists and 56.0% of general dentists sterilized new endodontic files before use. The study also showed that 50.0% of the respondents disinfected gutta-percha, with endodontists statistically more likely to do so than general dentists.[14] Two different studies in Nigeria and India had comparable results in regard to disinfecting gutta-percha.[15],[16] In both studies, most respondents did not disinfect new gutta-percha cones before obturation.[15],[16]

It is crucial to use an aseptic technique when preparing root canal systems to ensure the success of endodontic treatment and, most importantly, the patient's long-term health.[11] Roth et al. (2006) assessed the sterility of 150 new unused endodontic files as received from manufacturers and found that 13% of them had microbial contamination.[7] This result indicated that endodontic files are not sterile at the time of purchase, and sterilization should be done before first use.[7] On the other hand, our findings regarding the sterility status printed on the back of the new endodontic file packages revealed that 37.1% were unaware, 20.3% were aware and checked it, 20.8% forgot to check it most of the time, and 21.8% do not check it at all.

Failing to perform proper disinfection can have serious consequences. Several studies have been conducted to evaluate the risk of the transmission of sporadic Creutzfeldt–Jakob disease (sCJD) in endodontic practice.[17],[18]

In 2007, Bourvis et al. determined that the risk of sCJD transmission due to the reuse of endodontic instruments during root canal treatment is significant without an adequate decontamination process.[17] Walker et al. suggested discarding used endodontic instruments to reduce the risk of variant Creutzfeldt–Jakob disease transmission.[18]

In our study, we observed that a large number of the participants were reusing used endodontic files during subsequent treatments. Although the concept of single-use endodontic files remains controversial, some studies with substantial evidence emerged to advocate it.[19] The arguments included the difficulty in achieving adequate cleaning of the files,[20] risk of transmission of infection, and prior disease.[17],[18]

The respondents of this study used several decontamination methods to process used files. However, less than one-third of the respondents knew that ultrasonic cleaning is the best method for cleaning endodontic files, which is supported by the literature.[5] As for the sterilization technique for endodontic files, most of the respondents were aware of an autoclave. This aligns with the results of a previous study that showed that an autoclave is the most effective method for sterilizing endodontic files.[9]

The gutta-percha cones used in endodontic treatments are susceptible to microbial contamination during storage and manipulation. This produces aseptic conditions and has zinc oxide as one of its compositions which has a major role in antibacterial activity. Many researchers have aimed to guide dental practitioners and their staff on the importance of disinfecting gutta-percha.[21] An article was published in Portugal that evaluated the decontamination of gutta-percha cones contaminated with the bacteria Enterococcus faecalis using different concentrations of chlorhexidine digluconate (CHX) and NaOCl for short exposure times. The results concluded that 1.0% and 2.5% NaOCl and 2.0% CHX were effective for decontaminating the cones.[21]

Another article published in Brazil concluded that 2.5% NaOCl and 2.2% glutaraldehyde (”Cidex”) proved to be effective as sterilizing agents for gutta-percha cones.[22]

Most of the respondents in our study who did practice sterilizing gutta-percha cones used the method of immersion in 5.25% NaOCl for 1 min. Instruments and supplies that are sterilized and ready to use at dental clinics must be in a cabinet that is closed or covered. Before opening and using the packages of sterilized instruments, they should be checked to ensure that the packaging has not been compromised during storage. If wet, torn, or punctured during storage, the contents should be reprocessed before use.[23] More than half of the respondents believed that, after receiving a bag of sterile endodontic files and using only one of them, the other files were still sterile and could be kept to use for the next patients.

In a recent study by Merdad and Al-Ghamdi[8] the sterility of new endodontic K-type hand files as received from 5 different manufacturers was evaluated. The results of the study found that there was a bioburden on these files. In fact, these items are classified as “critical items” because they could come into contact with the body, pierce the oral mucosa, or enter the circulation.[24] The success of endodontic therapy and, more crucially, the patient's general health depend on the preparation of a root canal system using an aseptic procedure.[12]

The results of our study also suggest that some dental practitioners do not apply proper infection control measures for disinfecting new files and gutta-percha cones, despite having adequate knowledge. This finding could be due to negligence and lack of strict regulations at their institutions. However, many participants were unfamiliar with handling new endodontic files and assumed that they were sterile, as they responded with “I do not know” to the question about checking the sterility status on a file's package. These findings are in agreement with results from Nigeria[15] and India,[16] while there is disagreement with results from the United States[14] regarding the knowledge toward disinfecting new files and gutta-percha cones.

The overall level of knowledge regarding the sterility of new files and gutta-percha was disappointing. This observation is general and not limited to a certain dental school or practice. In addition, our results suggest that there are major variations in the methods of cleaning and sterilizing endodontic instruments. This suggests a lack of a clear standardized protocol for the sterilization of these instruments. As limitations of this study, small sample size was limited. Thus, increased the total number of study sample than the current number of study sample is necessary in this study design. This study covered only different institutes in Jeddah city, Saudi Arabia. It should be covered all dental centers, hospitals, and universities from different regions of the Kingdom of Saudi Arabia in future studies. Finally, it is recommended that written infection control guidelines are developed and distributed in the form of lectures and seminars at the local academic institutes.

  Conclusions Top

We found that the awareness of the sterility conditions of the new and unused endodontic files, gutta-percha, and their use in actual clinical practice among the participants in this study were not well adequate. Most of the sample used the new and unused files and gutta-percha received from a manufacturer's packaging without sterilization and/or disinfection before use in patients. This fact reflects their limited knowledge about the sterility of new files. On this basis, we recommend the development and implementation of written infection control guidelines regarding endodontic files. This information can then be distributed as lectures and seminars at the local academic institutes.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Kakehashi S, Stanley HR, Fitzgerald RJ. The effects of surgical exposures of dental pulps in germ-free and conventional laboratory rats. Oral Surg Oral Med Oral Pathol 1965;20:340-9.  Back to cited text no. 1
Sjögren U, Sundqvist G. Bacteriologic evaluation of ultrasonic root canal instrumentation. Oral Surg Oral Med Oral Pathol 1987;63:366-70.  Back to cited text no. 2
Prada I, Micó-Muñoz P, Giner-Lluesma T, Micó-Martínez P, Collado-Castellano N, Manzano-Saiz A. Influence of microbiology on endodontic failure. Literature review. Med Oral Patol Oral Cir Bucal 2019;24:e364-72.  Back to cited text no. 3
Walker JT, Dickinson J, Sutton JM, Raven ND, Marsh PD. Cleanability of dental instruments-implications of residual protein and risks from Creutzfeldt-Jakob disease. Br Dent J 2007;203:395-401.  Back to cited text no. 4
Jena D, Dash S, Jena SP, Singh NR, Kumari S. Sterilization in endodontics: A newer concept. Indian J Forensic Med Toxicol 2020;14:8356-9.  Back to cited text no. 5
Karamifar K, Tondari A, Saghiri MA. Endodontic periapical lesion: An overview on the etiology, diagnosis and current treatment modalities. Eur Endod J 2020;5:54-67.  Back to cited text no. 6
Roth TP, Whitney SI, Walker SG, Friedman S. Microbial contamination of endodontic files received from the manufacturer. J Endod 2006;32:649-51.  Back to cited text no. 7
Merdad KA, Alghamdi FT. Assessment of the sterility of new endodontic files received from the manufacturer using microbial culture and scanning electron microscopic analysis: An in vitro study. Cureus 2022;14:e28092.  Back to cited text no. 8
Zmener O, Speilberg C. Cleaning of endodontic instruments before use. Endod Dent Traumatol 1995;11:10-4.  Back to cited text no. 9
Dioguardi M, Sovereto D, Illuzzi G, Laneve E, Raddato B, Arena C, et al. Management of instrument sterilization workflow in endodontics: A systematic review and meta-analysis. Int J Dent 2020;2020:5824369.  Back to cited text no. 10
Ministry of Health. Manual of infection prevention & control in dental settings. In: Infection Prevention and Control, editor. Disease control and prevention infection control guidelines. Riyadh, Kingdom of Saudi Arabia: Ministry of Health, Kingdom of Saudi Arabia; 2018. p. 134.  Back to cited text no. 11
ADA. Sterilization or disinfection of dental instruments. J Am Dent Assoc 2001;132:785.  Back to cited text no. 12
Sjögren U, Figdor D, Persson S, Sundqvist G. Influence of infection at the time of root filling on the outcome of endodontic treatment of teeth with apical periodontitis. Int Endod J 1997;30:297-306.  Back to cited text no. 13
Banas JA, Lubinsky R, Qian F, Vickerman MM. A survey of sterilisation and disinfection practices for new endodontic files and gutta-percha in US dental offices. ENDO Endod Pract Today 2015;9:47-52.  Back to cited text no. 14
Enabulele J, Omo J. Sterilization in endodontics: Knowledge, attitude, and practice of dental assistants in training in Nigeria: A cross-sectional study. Saudi Endod J 2018;8:106-10.  Back to cited text no. 15
  [Full text]  
Panuganti V, Vivek V, Jayashankara C, Anilkumar S, Girish S, Nanjundasetty J. Gutta-percha disinfection: A knowledge, attitude, and practice study among endodontic postgraduate students in India. Saudi Endod J 2016;6:127-30.  Back to cited text no. 16
  [Full text]  
Bourvis N, Boelle PY, Cesbron JY, Valleron AJ. Risk assessment of transmission of sporadic Creutzfeldt-Jakob disease in endodontic practice in absence of adequate prion inactivation. PLoS One 2007;2:e1330.  Back to cited text no. 17
Walker J, Budge C, Vassey M, Sutton J, Raven N, Marsh P, et al. vCJD and the cleanability of endodontic files: A case for single use. ENDO Endod Pract Today 2009;3:115-20.  Back to cited text no. 18
Buchanan GD, Warren N. Single-use of endodontic hand files: Perceptions and practise. J Infect Prev 2019;20:32-6.  Back to cited text no. 19
Messer H, Parashos P, Moule A, Australian and New Zealand Academy of Endodontists. Should endodontic files be single-use only? A position paper from the Australian and New Zealand Academy of Endodontists. Aust Endod J 2003;29:143-5.  Back to cited text no. 20
Carvalho CS, Pinto MS, Batista SF, Quelemes PV, Falcão CA, Ferraz MA. Decontamination of Gutta-percha Cones employed in endodontics. Acta Odontol Latinoam 2020;33:45-9.  Back to cited text no. 21
da Motta PG, de Figueiredo CB, Maltos SM, Nicoli JR, Ribeiro Sobrinho AP, Maltos KL, et al. Efficacy of chemical sterilization and storage conditions of gutta-percha cones. Int Endod J 2001;34:435-9.  Back to cited text no. 22
National Center for Chronic Disease Prevention and Health Promotion. Summary of Infection Prevention Practices in Dental Settings: Basic Expectations for Safe Care. Atlanta, GA, USA: Division of Oral Health, Department of Health and Human Services, Centers for Disease Control and Prevention; 2016.  Back to cited text no. 23
National Health and Medical Research Council of Australia. Infection Control Guidelines for the Prevention of Transmission of Infectious Diseases in the Health Care Setting. Vol. 28; 2004.  Back to cited text no. 24


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