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 Table of Contents  
Year : 2022  |  Volume : 12  |  Issue : 3  |  Page : 236-252

Evolving trend of systematic reviews and meta-analyses in endodontics: A bibliometric study

1 Department of Dental Materials, Faculty of Dentistry, Asian Institute of Medicine, Science and Technology (AIMST) University, 08100, Bedong, Malaysia
2 Department of Family Oral Health, Faculty of Dentistry, Universiti Kebangsaan Malaysia, 50300, Kuala Lumpur, Malaysia
3 Batu 9 Dental Clinic, Ministry of Health Malaysia, 43200, Hulu Langat, Selangor, Malaysia
4 Bau Dental Clinic, Ministry of Health Malaysia, 94000, Bau, Malaysia
5 Petra Jaya Dental Clinic, Ministry of Health Malaysia, 93050, Kuching, Sarawak, Malaysia
6 Paediatric Dentistry Unit, School of Dental Sciences, Universiti Sains Malaysia, Health Campus, 16150, Kubang Kerian, Kelantan, Malaysia
7 Conservative Dentistry Unit, School of Dental Sciences, Universiti Sains Malaysia, Health Campus, 16150, Kubang Kerian, Kelantan, Malaysia

Date of Submission19-Oct-2021
Date of Decision27-Dec-2021
Date of Acceptance11-Feb-2022
Date of Web Publication1-Sep-2022

Correspondence Address:
Dr. Tahir Yusuf Noorani
Conservative Dentistry Unit, School of Dental Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian, Kelantan 16150
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/sej.sej_209_21

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Introduction: Endodontics is rapidly evolving with the emergence of various research publications. The present bibliometric study aimed to identify and analyze the trends of systematic reviews and meta-analyses in endodontics.
Materials and Methods: An electronic literature search using Scopus® and Web of Science databases was performed from January 2001 till August 2021. Only systematic reviews and meta-analyses published in English were retrieved. The following parameters were recorded and analyzed: Title, citation counts, authors, year of publication, institutions, countries, journals, type of article, source of articles, thematic categories, keywords, and source of fundings. Data were analyzed using Microsoft Excel software, Visualization of Similarities viewer software, and SPSS software with a significance level set at P = 0.05.
Results: Among the 149 articles included, the top-cited article was cited 184 times with 27 of them receiving more than 50 citations. 17 authors have contributed at least four publications, and most of the papers were published in 2020 (n = 26). Furthermore, the number of articles published increased substantially over the two decades (P < 0.05), but the citation counts decreased considerably (P < 0.05). The International Medical University Malaysia and the University of Hong Kong published the most articles, while Brazil was the most prolific country. The Journal of Endodontics published the most articles (n = 46) and more than half of the articles were published in Quartile 1 and Quartile 2 journals. The bulk of articles were published dealing with clinical or radiographic outcomes.
Conclusion: This study revealed significant information on the trends of systematic reviews and meta-analyses in endodontics providing a comprehensive understanding and direction of future research.

Keywords: Bibliographic database, citation analysis, dental informatics, endodontics, root canal

How to cite this article:
Lin GS, Leong JZ, Chong WX, Chee MC, Lee CS, Maqbool M, Noorani TY. Evolving trend of systematic reviews and meta-analyses in endodontics: A bibliometric study. Saudi Endod J 2022;12:236-52

How to cite this URL:
Lin GS, Leong JZ, Chong WX, Chee MC, Lee CS, Maqbool M, Noorani TY. Evolving trend of systematic reviews and meta-analyses in endodontics: A bibliometric study. Saudi Endod J [serial online] 2022 [cited 2022 Oct 3];12:236-52. Available from: https://www.saudiendodj.com/text.asp?2022/12/3/236/354827

  Introduction Top

Scientometrics, also referred to as scientific mapping, is a method of studying a vast body of bibliographic data and measuring various types of scientific activity that are frequently used in conjunction with data visualization. To examine the evolution of many disciplines in science, scientometricians have integrated numerous approaches from scientometrics, data visualization, and text analytics.[1] On the other hand, a bibliometric analysis is a statistical study of written publications that uses quantitative techniques to assess research subjects, research state, and publication quality.[2] Bibliometrics is also the study of strategies for retrieving and statistically analyzing quantifiable data in scholarly papers. It allows researchers to rapidly summarize and visualize the structure of a collection of publications and suggests prospective future research directions.[1]

Evidence-based healthcare necessitates up-to-date syntheses of existing evidence.[3] With the current advancement of technology, the appearance of new treatment options, new diagnostic tools, and the volume of articles with overwhelming amounts of new evidence, it is difficult for clinicians to incorporate research into practice as it is time-consuming.[4] Hence, systematic reviews are useful tools for clinicians, patients, and decision-makers to summarize and synthesize the available evidence related to diagnosis, therapy, and prognosis. Systematic reviews are described as reviews of the existing evidence on an explicitly articulated research topic that apply systematic techniques to identify and critically review selected studies, incorporate and synthesize the included research papers, as part of evidence-based healthcare studies.[5] This type of evaluation incorporated with meta-analysis is one of the most effective methods in translating knowledge into practice. It incorporates data from several studies using clear and transparent techniques, eliminating the need for decision-makers to review, interpret, and synthesize findings from multiple studies.[5],[6]

Endodontics has evolved tremendously in recent years, as seen by an increase in the number of articles in the endodontic literature. The first bibliometric analysis in endodontics was published in 2011, which identified the top 100 most-cited articles from five different endodontics-related journals.[7] Another bibliometric study was conducted later in 2015 to analyze and categorize papers published between 2009 and 2013 into sixteen thematic categories. It was observed that the number of reviews published in the two most prestigious endodontic journals (Journal of Endodontics and International Endodontic Journal) increased significantly, indicating a shift in the endodontic literature toward evidence-based endodontics.[8] Thus, identifying and analyzing trends of systematic reviews and meta-analyses in endodontics may aid in comprehending the field and direct future research. To the best of the author's knowledge, no bibliometric analysis has been conducted to determine the evolving trend of systematic reviews and meta-analyses in endodontics. Hence, the goal of the present analysis was to determine the characteristics of systematic reviews and meta-analyses in endodontics and offer insight into current and historical publishing patterns in the field.

  Materials and Methods Top

Search strategy

An electronic literature search using Scopus® and Thomas Reuter's Web of Science – Science Citation Index Expanded (SCIE) databases was conducted by two independent investigators (GSSL, JZL) in September 2021 to identify the published systematic reviews and meta-analyses in endodontics. The following search equation was applied: TITLE-ABS-KEY (((endodontics) OR (endodontic) OR (root AND canal) OR (root AND canals)) AND ((systematic AND review) OR (meta AND analysis))) and confined to the “final” stage of publication in the category of “Dentistry” and “Dentistry, Oral Surgery and Medicine” for Scopus® and Web of Science databases, respectively. Only systematic reviews with or without meta-analysis in the field of endodontics published in English between January 2001 and August 2021 were included. Original research articles, literature reviews, scoping reviews, umbrella reviews, case reports, case series, commentaries, editorials, letters to the editor, conference abstracts, and opinions were excluded. Furthermore, the number of publications and journals that may be included was not restricted. Any disagreements about articles that may be included or excluded during the search were discussed with the assistance of the third and fourth investigators (WXC, MCKC) who are senior investigators. The total citations, citation density, journal impact, and ranking of each selected article were determined using the Journal Citation Reports (JCR) and SCImago Journal and Country Rank (SJR) databases.

Data collection

Data extraction after the full-text assessment was performed by the other two investigators independently (CSL, MCKC). The following parameters were extracted from each article: Title of the articles, author's name (s), number of author (s), year of publication, institution (s) or affiliation (s), country (s), name of journal (s), types of articles, thematic categories, sources of articles, keywords, and number of citations. The authors' names were manually revised and normalized to avoid typographical, transcribing, and/or indexing flaws, as well as to standardize terminology. If more than one entry for the same author was found, the author's institutional affiliations were checked to determine if the entries belonged to the same individual. The articles were sorted in descending order based on the number of citations they received. If two articles had the same citation number, the one with a higher impact factor (IF) or JCR score was ranked first. The number of articles published was also used to rank the institutions, countries, and journals.

The types of articles were divided into either systematic review only or systematic review with meta-analysis. Each article was further classified into twelve thematic categories, including microbiology, pulp biology or pathology, root canal morphology, chemical preparation, mechanical preparation and instrumentation, working length determination, obturation, endodontic materials, restorations, endodontic surgery, epidemiological studies, and clinical or radiographic outcomes.[8] Articles that did not fall into one of these categories were classified as “others.” The classification of thematic categories was calibrated for all four investigators (JZL, WXC, MCKC, CSL), and any discrepancies were discussed with the fifth and sixth investigators (GSSL, TYN). The first author's affiliation was used to determine the sources of the article. They were also divided into “academic” for research publications from universities and “non-academic” for articles from private practices or groups. Each article's financial source was also listed.

Data analysis

Descriptive analysis was performed using the Microsoft Excel software (One Microsoft Way Redmond, WA 98052-6399, USA). The Visualization of Similarities viewer (VOSviewer) software (VOSviewer v. 1.6.15; Centre for Science and Technology Studies, Leiden University, Netherlands) was used to create bibliographic networks based on co-authorships and keyword co-occurrences. The minimum number of articles by an author was set to two, while the minimum number of co-occurrences of keyword was set to eight. The size of the node showed how often co-authorships or keyword co-occurrences occurred. Meanwhile, the colors of the nodes reflect the various clusters to which the analyzed objects belonged. A t-test was performed with a significant level set at P = 0.05 to assess the possible significant differences in publication and citation count parameters over two timeframes (2001–2010 and 2011–2021). Data analysis was performed using SPSS version 24.0 software (IBM, Armonk, NY, USA).

  Results Top

A total of 184 articles were chosen from primary research, but only 149 of the 184 articles were eligible for further analysis after a thorough full-text assessment. [Table 1] shows all the 149 articles sorted by the number of citations in descending order. The article with the most citations was “Outcomes of nonsurgical retreatment and endodontic surgery: A systematic review,” cited 184 (Scopus) and 153 (WOS) times, with a citation density of 15.33.[9] This is followed by the second most-cited article entitled “Outcome of secondary root canal treatment: A systematic review of the literature” with 182 (Scopus) and 168 (WOS) citations, and a citation density of 14.[10] The third most-cited article was “Tooth survival following non-surgical root canal treatment: A systematic review of the literature” with 182 (Scopus) and 159 (WOS) citations, and a citation density of 16.55.[11] In addition, five articles were found to have a citation density >15,[12],[13],[14],[15],[16] despite not being the top-three most-cited articles. Only 27 of the chosen articles received more than 50 citations, making them citation classics, and ranking in the top 18.1%. On the other hand, 20 articles had no citation.
Table 1: The most-cited articles based on the citation counts

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Authors, year of publication, institutions, country

Lists the authors [Table 2] who have published at least four articles on systematic review and metal analysis in endodontics [Appendix 1][Additional file 1]. A total of 17 authors had contributed at least four publications. The author with the greatest number of publications was Shane N. White (8 articles), followed by Venkateshbabu Nagendrababu (7 articles), and Emmanuel João Nogueira Leal Silva (6 articles) [Figure 1]a. In contrast, Mahmoud Torabinejad was the first author with the most publications (n = 5), followed by Jorge N. R. Martins and Prasanna Neelakantan, each with four articles as first author [Figure 1]b. The trend of authorships among the selected articles is illustrated in [Figure 2], with the mean number of authors being 4.9, the median being 5, and a range of 1–13 authors. The state-wise distribution of publications also revealed the maximum number of authors was 6 (22.1%), followed by five authors (20.3%) and three authors (17.4%). A collaboration network was created for co-authors who contributed two or more articles from the chosen article list [Figure 3]. Among the 583 authors, only 29 authors met the threshold. The node size represents the number of articles each author has published, while the joining lines reflect the strength of their cooperation. The co-authorship bibliometric network revealed four distinct clusters, with Nagendrababu V representing the biggest node.
Table 2: Authors with at least four articles published on systematic review and meta-analysis related to endodontics

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Figure 1: (a). Authors with five or more articles published. (b). First authors with at least three articles published

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Figure 2: Trends of authorships among the selected articles

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Figure 3: Graphical mapping of co-authorships with at least two publications co-occurrence using the VOSviewer Software. The node sizes of the authors reflect the number of scientific articles they contributed. The links between each author represents the number of co-authorships. Five well-differentiated clusters can be observed including Neelakantan, P. (red), Silva, E.J.N.L (blue), Nagendrababu, V. (green), Rossi-Fedele, G. (yellow), and Setzer, F.C. (purple)

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The overall number of citations and the number of articles by year of publication is illustrated in [Figure 4]. The highest number of publications was noted in the year 2020 with 26 articles published, followed by 2018 and 2019, each with twenty articles. On the other hand, the least number of publications were found in the years 2001, 2005 and 2009, each with one article published. The year 2007 had the largest number of total citations (n = 600), followed by 2008 (n = 527) and 2010 (n = 425). When comparing the first decade (years 2001–2010) to the second decade (years 2011–2021), the number of publications increased dramatically (P < 0.05), but the total number of citations decreased substantially (P < 0.05). Furthermore, the overall citations count displayed an inconsistent pattern over the years, with a sharp decline beginning in 2017. [Table 3] shows that fifteen institutions produced five or more related publications, with the International Medical University Malaysia and The University of Hong Kong producing the most (each with eight articles), followed by the Rio de Janeiro State University and the University of Milan (each with six articles), and the remaining institutions producing five articles each. Moreover, sixteen countries have published at least five systematic reviews with or without meta-analysis in endodontics [Table 3], with Brazil (n = 40) contributing the most articles, followed by the United States (n = 34), China (n = 15), Malaysia (n = 13), and Australia (n = 12).
Table 3: Institutions, countries, and journals with at least five articles published on systematic reviews and meta-analyses in endodontics

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Figure 4: Number of publications and total citation counts with regards to the year of publication

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Journals ranking, impact factor scores, Journal Citation Reports scores

The 149 articles included in this study are published by 22 journals [Appendix 2][Additional file 2]. Journals in which the articles were published were ranked in descending order. Journals with a similar number of published articles were ranked based on their IF or SJR scores. IF and SJR are parameters that were used for the calculation of citations from the Web of Science and Scopus databases, respectively. [Table 3] presents the list of journals that published at least five articles, with the Journal of Endodontics publishing the most with 46 publications (29.5%), followed by the International Endodontic Journal with 26 articles (17.4%), and Clinical Oral Investigation with six articles (4.0%). Out of the 149 articles chosen, 87 were published in journals related to endodontics [Figure 5]a. The Journal of Endodontics published the greatest number of articles with a total of 46 (52.9%) publications. Following that, the International Endodontic Journal contributed 26 articles (29.9%), the Australian Endodontic Journal and the Iranian Endodontic Journal each contributed five articles (5.7%), the European Endodontic Journal contributed three articles (3.4%), and the Dental Press Endodontics and the Giornale Italiano di Endodonzia each contributed one article (1.2%)
Figure 5: (a). The number of selected articles published in endodontic related journals. (b). Classification of the selected articles based on SCImago Journal Rank 2020 in quartiles. (c). Classification of the selected articles based on Journal Citation Reports 2020 in quartiles

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According to the SCImago Journal Rank [Figure 5]a. 108 articles (72.5%) were presented in Quartile 1, 22 articles (14.8%) in Quartile 2, 12 articles (8.1%) in Quartile 3, 5 articles (3.4%) in Quartile 4, and finally, 2 articles (1.2%) were derived from journals no longer indexed in the Scopus database. In contrast, based on the JCR (IF) scores [Figure 5]b, 85 articles (57%) were presented in Quartile 1, 17 articles (11.4%) in Quartile 2, 5 articles (3.4%) in Quartile 3, 8 articles (5.4%) in Quartile 4. The remaining 34 articles (22.8%) were published in journals, not on the SCIE journal list.

Article types, thematic categories, source of articles, keywords, source of fundings

Among all the selected articles, 56 articles (37.6%) were systematic reviews only, while the remaining 93 articles (62.4%) were systematic reviews with meta-analysis [Table 4]. As for the thematic category, the clinical or radiographic outcome theme contributed the highest number of articles (n = 30), followed by mechanical preparation and instrumentation (n = 19), chemical preparation (n = 16), and epidemiological studies (n = 14). However, working length determination, restoration, and pulp biology or pathology are among the themes with the least amount of publication, with each contributing two articles. Furthermore, the department of endodontics was the most prolific, with 46 articles, followed by 17 articles from the department of restorative dentistry and seven articles from the department of oral medicine and oral pathology. Only three articles were labeled as “non-academic” from all the articles included. The sources of finding are listed accordingly with the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES Foundation) Brazil contributed the most [Appendix 3][Additional file 3]. When the minimum number of co-occurrences of keywords was set to eight, 884 keywords were discovered. There were 58 that met the standards, with the top four keywords being “human,” “meta-analysis,” “systematic review,” and “endodontics” [Figure 6].
Table 4: Article types, thematic categories, and the source of articles

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Figure 6: Graphical mapping of keywords using VOSviewer software with at least eight keywords co-occurrence. Lager nodes represent keywords with a more frequent appearance of which “human” is the central node. The small distance between two terms represents that a large number of co-occurrences of the terms. Well-differentiated clusters can be observed including “human” (blue), “meta-analysis” (red), “review” (green), and “root canal therapy” (yellow)

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  Discussion Top

The current study is the first of its kind to analyze and compare the trends and bibliometric indices of systematic reviews and meta-analyses in endodontics over the last two decades. Even though systematic reviews and meta-analyses have long been thought to represent the highest level of evidence, the top-cited article earned 184 citations,[9] and fewer than 20% of the review articles received 50 or more citations, which is lower than prior bibliometric analyses on endodontics, where the top-cited articles received more than 500 citations.[7],[17],[18] Although an article cited more than 100 times can be deemed a classic, in some specific disciplines with limited scholars, the author believes that 50 citations may suffice. The possible explanations as to why systematic reviews and meta-analyses in the field of endodontics are under-cited, including a delay in the accrual of citations, notably beginning in 2018. Furthermore, high-quality endodontic systematic reviews may opt to be published in non-dental journals, such as the BioMed Research International journal,[18] which have higher IFs than other dentistry journals. Notwithstanding, since the dental field is typically smaller than the medicine and health sciences, it is questionable to directly compare IFs of journals in various areas. Although systematic reviews offer a higher level of evidence, these publications primarily summarize the current literature.[19] As a result, the authors speculated that when a new research paper intends to describe its findings and draws a comparison to existing literature, the original article is frequently cited. In addition to the chance of a review article being cited, editors of journals also tend to take into account the review's readership, hence leading to lower citation count.[20]

An intriguing finding is that some authors were not listed as the first author, yet they contributed to most publications. Although the findings of the current study suggest that first authorship may not possess a barrier to publishing articles in endodontics, it is still disputed whether co-authorship accurately reflects real contribution. Given that authorship attribution standards may have developed over time, roles such as senior scientist, mentor, lab director, technician, and statistician that were previously not awarded with authorship may now be awarded with authorship.[21] Furthermore, performance assessment policies could be one of the factors of rising co-authorship. Therefore, dubious co-authorship practices could be a result of demands to publish those researchers and policymakers are oblivious to.[22] Nonetheless, the average number of authors per paper reflected a multidisciplinary approach and a growing interest among researchers from diverse institutes and nations.[23] On the other hand, the co-authorship network map indicated a dearth of shared edges between neighboring nodes or clusters, highlighting more future collaboration opportunities as separate research groups with various cluster colors do not collaborate. Collaboration within research networks is essential because it allows researchers to share their expertise and discoveries, making them more efficient, productive, and less repetitious in their work.[24]

The current findings show a dramatic surge of publication in the second decade (years 2011–2021). Such a rise could be due to endodontic advancements in recent years, which have allowed for more well-designed research and systematic reviews. A vast number of systematic reviews were published in the year 2020 which may be attributed to an increase in the quantity and quality of conservative and endodontics researchers, a better understanding of systematic review protocol, and widespread interest among researchers in collaborative work.[7],[8] One interesting finding of this study is that the year 2007 had the highest amount of citation counts. It is indeed predictable that papers published in 2021 earn no citations, but it's unclear if citations will increase over time and peak in the coming years. This could be one of the shortcomings of the present analysis as it included articles published in recent years. Moreover, some key articles may not be readily recognized as citation classics despite their publication history since their scientific topic has become so well-known that it is no longer acknowledged.

The Journal of Endodontics published the most articles, which is consistent with other endodontic-related bibliometric analyses.[17],[24] Future readers and researchers interested in systematic reviews and meta-analyses pertaining to endodontics will be able to focus their efforts on this key journal. Only three journals (7.5%) published more than five articles, whereas 19 journals (47.5%) published only one review article. This indicates that while many journals contributed to the publication of systematic reviews in endodontics, only a few journals insisted on publishing relevant research.[25] The two most prolific endodontic journals were the Journal of Endodontics and the International Endodontic Journals, with overall SJR and IF scores ranging from 1.850–1.988 to 4.171–5.264, respectively, suggesting that high-impact endodontic journals publish systematic reviews and meta-analyses more frequently. The journal's high IF also shows its relevance as a source of knowledge for endodontic researchers interested in systematic reviews and meta-analyses.[26] Surprisingly, the Clinical Oral Investigation was placed third in the number of review articles published, indicating that not all endodontic articles are published in endodontic journals. The journal's aim and scope, which favors studies with a high level of evidence, its high IF and SJR scores, rapid review status, higher acceptance rates compared to other journals, and more social media dissemination are all possible explanations for this occurrence. Therefore, these increase the likelihood of the Clinical Oral Investigation journal in drawing attention.

Brazil was ranked first among other nations in terms of the number of publications in endodontics which is in accordance with a previous study,[27] with the United States coming in second. The United States' position was predicted, given it corresponded to the previous findings.[7] Brazil, China, and Malaysia showed a significant scientific contribution in systematic reviews and meta-analyses, indicating that endodontics knowledge is growing fascinatingly in non-English speaking countries where language may not be a major obstacle.[28] Furthermore, publications from funding organizations or partners in developed countries may be indexed as collaborative research, and therefore, developed countries' top researchers and research funding organizations may need to work more closely with developing countries to boost up their research output.[29] Interestingly, International Medical University Malaysia and The University of Hong Kong contributed the most articles, with eight articles each. This highlights the potential of Asian countries to produce systematic reviews and meta-analyses related articles which corroborates with previous bibliometric analysis.[8]

More than half of the selected reviews comprised meta-analysis, implying that researchers are becoming aware of the value of meta-analysis as a tool for validating or debunking disputed findings from numerous studies. In terms of thematic category, the bulk of the publications dealt with the clinical and radiographic outcome, followed by mechanical and instrumentation, and chemical preparation which contradicts previous bibliometric studies.[7],[8] This might be due to a need for clinicians to have a greater understanding on how endodontic therapy is improving, with more predictable outcomes and fewer postendodontic complications for patients. On the other hand, working length determination, restoration and pulp biology or pathology are among the least popular fields, which may be due to the restricted primary study available to conduct this sort of review. Hence, future systematic reviews should explore further into these contexts in order to offer clinicians more trustworthy and credible evidence. Moreover, a large number of articles were categorized as “other” since they could not be classified in any of the 16 thematic categories relevant to the subject of research.

The discovery that a high number of review articles in the endodontic literature appeared to originate from endodontics-related departments of academic institutions, which contradicted a previous analysis,[8] was of considerable interest. Academic institutions where the endodontic department is integrated within the “restorative,” or “preventive dentistry” department are more common in European countries.[8] However, most papers in the current analysis originated from non-European nations, hence, it is reasonable to assume that the terms “endodontics” and “endodontology” are included in their department determination. Keywords generally reflected the studies' themes of interest and techniques by using the VOS software to indicate the research trend line. The VOS software eliminated generic phrases unrelated to the specific topic and selected the most relevant keywords from the chosen articles to retain the focus on more useful terms.[30] As a result, the keywords discovered in this study may properly represent how research in the field of minimally invasive access cavities has been conducted.

The highest level of evidence in the hierarchy of evidence is systematic reviews and meta-analyses, labeled as “level I.”[31] The current study has the advantage of providing level I publications, which have the highest level of evidence-based knowledge in endodontics. Furthermore, endodontic articles were commonly published in general dental journals. The inclusion of such a diverse variety of journals allows the current bibliometric analysis to be relevant and credible. Several limitations in the current bibliometric analysis were also identified. First, only two databases (Scopus and Web of Science) were used, and the linguistic medium was confined to English. This means that publications that were not found in both databases, as well as those written in languages other than English, were excluded from the analysis. Second, since the institutional addresses used in the current study were limited to institutions and countries where the authors worked/were employed at the time the research was performed or the paper was written, only those institutions and countries received acknowledgment.

Third, the time frame chosen for the present analysis appears to be rather recent. As a result, the time factor would have a significant influence, as freshly published papers, regardless of their content or quality, obviously have a disadvantage of inadequate time to accrue a significantly higher number of citations.[32] Besides, a citation count as a valid tool to assess a scientific publication may not be adequate. However, several factors impact an article's citation count, including the author's reputation and the journal chosen for citation. These considerations indicate that citation count acts as an adversary in terms of being an unbiased mirror of a manuscript's quality and impact.[33] Moreover, the specific use of keywords in the current analysis may limit search results and future studies should explore different keywords during the primary search of articles.

  Conclusion Top

Within the limitations, this present bibliometric study offers valuable information regarding systematic reviews and meta-analyses in the field of endodontics. With 17 authors contributing at least four publications, 18.1% of the chosen review articles were designated citation classics. Over the last two decades, there has been a constant increase in research publications. The bulk of articles came from Brazil, and the Journal of Endodontics remains the most popular journal among researchers. Moreover, more than half of the selected systematic reviews comprised of meta-analyses, and the most prominent topic of interest was clinical or radiographic outcomes.

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Conflicts of interest

There are no conflicts of interest.

  References Top

Chandra Y. Mapping the evolution of entrepreneurship as a field of research (1990-2013): A scientometric analysis. PLoS One 2018;13:e0190228.  Back to cited text no. 1
Lei F, Ye J, Wang J, Xia Z. A bibliometric analysis of publications on oxycodone from 1998 to 2017. Biomed Res Int 2019;2019:9096201.  Back to cited text no. 2
Muka T, Glisic M, Milic J, Verhoog S, Bohlius J, Bramer W, et al. A 24-step guide on how to design, conduct, and successfully publish a systematic review and meta-analysis in medical research. Eur J Epidemiol 2020;35:49-60.  Back to cited text no. 3
Gopalakrishnan S, Ganeshkumar P. Systematic reviews and meta-analysis: Understanding the best evidence in primary healthcare. J Family Med Prim Care 2013;2:9-14.  Back to cited text no. 4
[PUBMED]  [Full text]  
Fernandes S, Jit M, Bozzani F, Griffiths UK, Scott JA, Burchett HE. A bibliometric analysis of systematic reviews on vaccines and immunisation. Vaccine 2018;36:2254-61.  Back to cited text no. 5
Carrasco-Labra A, Brignardello-Petersen R, Glick M, Guyatt GH, Azarpazhooh A. A practical approach to evidence-based dentistry: VI: How to use a systematic review. J Am Dent Assoc 2015;146:255- 65.e1.  Back to cited text no. 6
Fardi A, Kodonas K, Gogos C, Economides N. Top-cited articles in endodontic journals. J Endod 2011;37:1183-90.  Back to cited text no. 7
Tzanetakis GN, Stefopoulos S, Loizides AL, Kakavetsos VD, Kontakiotis EG. Evolving trends in endodontic research: An Assessment of published articles in 2 leading endodontic journals. J Endod 2015;41:1962-8.  Back to cited text no. 8
Torabinejad M, Corr R, Handysides R, Shabahang S. Outcomes of nonsurgical retreatment and endodontic surgery: A systematic review. J Endod 2009;35:930-7.  Back to cited text no. 9
Ng YL, Mann V, Gulabivala K. Outcome of secondary root canal treatment: A systematic review of the literature. Int Endod J 2008;41:1026-46.  Back to cited text no. 10
Ng YL, Mann V, Gulabivala K. Tooth survival following non-surgical root canal treatment: A systematic review of the literature. Int Endod J 2010;43:171-89.  Back to cited text no. 11
Pak JG, White SN. Pain prevalence and severity before, during, and after root canal treatment: A systematic review. J Endod 2011;37:429-38.  Back to cited text no. 12
Gillen BM, Looney SW, Gu LS, Loushine BA, Weller RN, Loushine RJ, et al. Impact of the quality of coronal restoration versus the quality of root canal fillings on success of root canal treatment: A systematic review and meta-analysis. J Endod 2011;37:895-902.  Back to cited text no. 13
Sarkis-Onofre R, Skupien JA, Cenci MS, Moraes RR, Pereira-Cenci T. The role of resin cement on bond strength of glass-fiber posts luted into root canals: A systematic review and meta-analysis of in vitro studies. Oper Dent 2014;39:E31-44.  Back to cited text no. 14
Torabinejad M, Nosrat A, Verma P, Udochukwu O. Regenerative endodontic treatment or mineral trioxide aggregate apical plug in teeth with necrotic pulps and open apices: A systematic review and meta-analysis. J Endod 2017;43:1806-20.  Back to cited text no. 15
Silva Almeida LH, Moraes RR, Morgental RD, Pappen FG. Are premixed calcium silicate-based endodontic sealers comparable to conventional materials? A systematic review of in vitro studies. J Endod 2017;43:527-35.  Back to cited text no. 16
Yılmaz B, Dinçol ME, Yalçın TY. A bibliometric analysis of the 103 top-cited articles in endodontics. Acta Odontol Scand 2019;77:574-83.  Back to cited text no. 17
Karobari MI, Maqbool M, Ahmad P, Abdul MS, Marya A, Venugopal A, et al. Endodontic microbiology: A bibliometric analysis of the top 50 classics. Biomed Res Int 2021;2021:6657167.  Back to cited text no. 18
Aromataris E, Fernandez R, Godfrey CM, Holly C, Khalil H, Tungpunkom P. Summarizing systematic reviews: Methodological development, conduct and reporting of an umbrella review approach. Int J Evid Based Healthc 2015;13:132-40.  Back to cited text no. 19
Ketcham CM, Crawford JM. The impact of review articles. Lab Invest 2007;87:1174-85.  Back to cited text no. 20
Fanelli D, Larivière V. Researchers' Individual publication rate has not increased in a century. PLoS One 2016;11:e0149504.  Back to cited text no. 21
Fanelli D, Costas R, Larivière V. Misconduct policies, academic culture and career stage, not gender or pressures to publish, affect scientific integrity. PLoS One 2015;10:e0127556.  Back to cited text no. 22
Adnan S, Ullah R. Top-cited articles in regenerative endodontics: A bibliometric analysis. J Endod 2018;44:1650-64.  Back to cited text no. 23
Shamszadeh S, Asgary S, Nosrat A. Regenerative endodontics: A scientometric and bibliometric analysis. J Endod 2019;45:272-80.  Back to cited text no. 24
Shi J, Gao Y, Ming L, Yang K, Sun Y, Chen J, et al. A bibliometric analysis of global research output on network meta-analysis. BMC Med Inform Decis Mak 2021;21:144.  Back to cited text no. 25
Abraham S, Mehta DL, Bellad SC, Patil S, Kamble AB, Chaudhari S. The contribution of indian endodontists in rotary endodontics to pubmed database, from 2000-2017. Open Access Maced J Med Sci 2018;6:1878-81.  Back to cited text no. 26
Aksoy U, Küçük M, Versiani MA, Orhan K. Publication trends in micro-CT endodontic research: A bibliometric analysis over a 25-year period. Int Endod J 2021;54:343-53.  Back to cited text no. 27
Dmytriw AA, Hui N, Singh T, Nguyen D, Omid-Fard N, Phan K, et al. Bibliometric evaluation of systematic review and meta analyses published in the top 5 “high-impact” radiology journals. Clin Imaging 2021;71:52-62.  Back to cited text no. 28
Fontelo P, Liu F. A review of recent publication trends from top publishing countries. Syst Rev 2018;7:147.  Back to cited text no. 29
Silva EJNL, Pinto KP, Ajuz NC, Sassone LM. Ten years of minimally invasive access cavities in Endodontics: A bibliometric analysis of the 25 most-cited studies. Restor Dent Endod 2021;46:e42.  Back to cited text no. 30
De la Flor-Martínez M, Galindo-Moreno P, Sánchez-Fernández E, Piattelli A, Cobo MJ, Herrera-Viedma E. H-classic: A new method to identify classic articles in Implant Dentistry, Periodontics, and Oral Surgery. Clin Oral Implants Res 2016;27:1317-30.  Back to cited text no. 31
Feijoo JF, Limeres J, Fernández-Varela M, Ramos I, Diz P. The 100 most cited articles in dentistry. Clin Oral Invest 2014;18:699-706.  Back to cited text no. 32
Ahmad P, Alam MK, Jakubovics NS, Schwendicke F, Asif JA. 100 years of the Journal of Dental Research: A bibliometric analysis. J Dent Res 2019;98:1425-36.  Back to cited text no. 33


  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]

  [Table 1], [Table 2], [Table 3], [Table 4]


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