Bibliometric analysis of correlations between adverse effects of metal release and orthodontic materials

Introduction

Orthodontic treatment, a cornerstone of modern dentistry, relies heavily on the use of various orthodontic materials to correct malocclusions and enhance dental aesthetics.¹ Metal alloys especially those containing nickel and titanium—are frequently used in orthodontics because of their favorable mechanical qualities and biocompatibility.² However, the potential concerns regarding negative consequences which related to the discharge of metal ions from these materials into the oral cavity.³ The metal ions release from orthodontic products has become more interested in the dentistry scientific community.⁴ According to studies, ions including nickel, chromium, and other elements may be released into the saliva as well as surrounding tissues as a result of the corrosion and deterioration of metal orthodontic components.⁵ The safety and biocompatibility of orthodont this phenomena, especially in individuals who have metal sensitivity or other allergies.⁶ A useful method for statistically assessing research trends, publishing patterns, and the influence of scientific literature in a particular topic is bibliometric analysis, which has gained popularity in recent years.⁷ Bibliometric studies can offer significant insights into the present state of knowledge, recognize important research concepts, and highlight fields for further investigation by methodically examining the body of literature currently available on the relationships between orthodontic materials and the negative effects of metal release.⁸ In order to better understand the state of the research in this field, this study intends to provide a thorough bibliometric analysis of the connections between orthodontic materials and the negative consequences of metal release. This study aims to identify important research trends, significant publications, and new areas of interest pertaining to the safety and biocompatibility of orthodontic materials in connection to metal ion release by synthesizing and evaluating the body of current literature.

Material and methods

Bibliometrics is a statistical analysis tool that provides quantitative information on scholarly literature.^9,10 According to Van Raan (2005),¹¹ bibliometric analysis provides insight into the evolution of the body of knowledge within a specific field by reviewing data from databases such as citations, authors, keywords, and the frequency with which publications are read. Bibliometrics employs a range of methods, such as co-citation analysis, bibliographic coupling, citation analysis, and co-word analysis for keywords, depending on the type of data used in the study.^9,12

Data source and search strategy

On Febraury 19, 2024, we obtained the required data from the Scopus data system. To do this, we performed a targeted search on Scopus, concentrating on the orthodontic alloy and its relationship to corrosion in particular in the titles. Data mining and a worldwide trend analysis were our goals. For this, keywords that were carefully chosen were employed. At first, 1321 publications that were released between 2013 and 2023 were found. However, we eliminated any publications released on or before 2013 to prevent outdated data in order to guarantee the applicability and currency of the material acquired. The query string “(TITLE-ABS (ABS“orthodontics alloy*corrosion”))” was used throughout the selection process.

Using this search strategy, we thoroughly investigated a number of bibliometric features connected to these data. Document type; accessibility status (open or restricted); number of citations; average number of citations per document; H-index; highly cited documents; global distribution of publications; productivity leaders; prestigious institutions and journals; international cooperation; frequently used terms in titles and abstracts; frequently used keywords; bibliographic coupling; and journal co-citations were among the topics we investigated. We utilized the VOSviewer software (version 1.6.18) ¹³ to show the links between terms, keywords, and nations, as well as the journal co-citation density and bibliographic coupling. The process of creating visual representations that show how these elements relate to one another was made easier by this program.

Bibliometric maps

We exported author keywords, bibliographical information, and citation data from 1321 articles to VOSviewer, version 1.6.18. The purpose of this software, VOSviewer, is to create and display bibliometric maps. The ability of VOSviewer to create bibliometric maps which will be discussed in the following sections of this study to visualize bibliometric data is well known. The exported bibliometric maps from VOS Viewer will be used to show author keyword associations and co-authorship trends. The maps incorporate different aspects in accordance with the instructions provided in the VOS Viewer documentation. This study’s principal items of interest are countries and author keywords. These items have the potential to be linked or related. A positive numerical value called the strength is assigned to each connection, denoting the strength of the relationship between the linked objects. A stronger relationship is indicated by a greater strength number. The number of articles co-authored by a country is represented by its link strength in the co-authorship analysis. Furthermore, the complete strength of a nation’s co-authorship relationships with other nations is shown by its overall link strength. Similarly, in co-occurrence analysis, the strength of the association between author keywords indicates how frequently those two keywords occur together in articles.¹⁴

Analysis of co-authorship

We considered a thorough list of 43 nations linked to 160 writers in our co-authorship study. Africa, America, Asia, Europe, and Oceania were the five major continents into which these

Analysis of co-occurrence

Using a dataset of 1,321 articles, we looked at 181 author keywords to do the co-occurrence analysis. Following the methodology used in the co-authorship study, we first created a thesaurus file to make sure that identical author terms don’t interfere with the co-occurrence analysis. We set the minimum keyword occurrence requirement for analysis in VOSviewer to be at least 5. To illustrate important factors, such as the average publishing year, frequency of occurrences, and strength of linkages between terms, we used the overlay visualization style. The average publication year of the publications containing each keyword is indicated by its color in this graphic. This method helps to comprehend the time aspect of the keywords’ significance in the literature that has been examined.

Results and discussion

Research Interest in Publication Output and Growth

Over a ten-year period, 1,321 research articles were published Figure 1. In 2014, we saw a decrease in publications—just 19 articles were published. There was a minor uptick to 20 publications in 2015, however, the number significantly decreased to 16 publications in 2016. In 2017, the decline persisted and reached a low of 14 publications. But in 2018 and 2019, the number of publications started to increase once more, with 19 articles published year. At its height in 2020, the trend had 24 publications. In contrast, a decrease was observed in 2023, the study’s final year. Generally, during the study period, there were fluctuations in the number of annual publications.

Preferred Journals

Based on our analysis, the top 10 most productive journals in the orthodontic alloys and corrosion topic are listed in Table 1 and are published by eight different publishers. Elsevier is the most well-known publisher among them, and it has three journals on the list: International Orthodontics, Materials Science and Engineering C, and Surface and Coatings Technology. The Russian Association of Corrosion Engineers, Allen Press, Jaypee Brothers Medical Publishers, Dental Press International, the Engineers Society of Corrosion in Belgrade, and the Multidisciplinary Digital Publishing Institute (MDPI) are the publishers of the remaining periodicals. With 41,237 papers published, Materials, published by MDPI, is the most productive journal, accounting for 5.8% of all publications in this subject. The publications published by Elsevier and Allen Press, Surface and Coatings Technology (11,472, 10%) and Angle Orthodontist (1,448, 6.4%), come next. With 52 citations overall, Surface and Coatings Technology from Elsevier is noteworthy for having the most citations, with one of its publications receiving the most citations.

This paper, “TiN coated stainless steel bracket: Tribological, corrosion resistance, biocompatibility and mechanical performance,” demonstrates Elsevier’s noteworthy influence in the filed. Three journals have a CiteScore of 5 or above, per the CiteScore 2023 report. Materials Protection has the lowest CiteScore of 0.8, while Materials Science and Engineering C has the highest CiteScore of 12.6. Materials Protection has only 193 articles and is rated eighth in Scopus, yet its CiteScore and total citations are far lower than those of other journals. This is probably because of its smaller readership and specialized focus. It is important to remember that, although while CiteScore is a helpful indicator for evaluating journal impact, picking a journal for publishing shouldn’t be based only on it. It’s important to take into account other elements including audience reach, journal repute, and relevance to the particular subject of study. Our results enable researchers to make well-informed decisions on journal selection by giving them useful information about possible journals to which they should submit their work on orthodontic alloys and corrosion.

Table 2 lists the top 15 most productive countries for orthodontic alloy and corrosion research. These countries contribute significantly to global research production, with India, Brazil, and China ranking first through third. India leads the chart with 46 papers, accounting for 16% of all publications in this field, emphasizing its essential role in promoting orthodontic alloy research. Brazil and China follow closely behind, each accounting for 10% of total articles. These three countries account for over 36% of global research output, highlighting their critical position in this field. With 9% of all articles produced, the United States comes in fourth place, largely because to universities like Marquette University School of Dentistry. With contributions ranging from 3% to 8% of the total articles, Japan, Germany, Taiwan, Croatia, and Italy are among the other noteworthy contributors. Remarkably, a number of European nations, including Greece, Croatia, Italy, and Germany, are represented, suggesting that orthodontic alloys and corrosion are subjects of intense interest and research throughout Europe. The percentage of single-country publications (SCPs) offers intriguing information about intra-country cooperation. Strong domestic collaboration networks are shown by the significant percentage of single-country publications (16%), (10%), and (10%) from China, Brazil, and India.

Greece, on the other hand, exhibits a high level of international collaboration as seen by its substantial number of co-authored papers with other nations, while having just 11 SCPs and a total connection strength of 15. The findings show that nations with higher SCP percentages have well-established local research networks, whereas those with lower SCP percentages participate in more international collaborations. For example, despite its low SCP rate, Greece is a hub of international research cooperation, accounting for 5% of total publications, primarily through partnerships with other countries.

The top 20 academic institutions in the sector in terms of productivity are shown in Table 3. With 11 publications, the National and Kapodistrian University of Athens in Greece tops the list. University of Zagreb and the Faculty of Medicine, University of Rijeka in Croatia follow with 10 publications apiece. The dominance of Croatian universities in this field indicates how important a role they have played in developing corrosion and orthodontic alloys research. The top 20 academic institutions in the sector in terms of productivity are shown in Table 3. With 11 publications, the National and Kapodistrian University of Athens in Greece tops the list. University of Zagreb and the Faculty of Medicine, University of Rijeka in Croatia follow with 10 publications apiece. The dominance of Croatian universities in this field indicates how important a role they have played in developing corrosion and orthodontic alloys research. The topic of orthodontic alloys and corrosion is greatly advanced by international collaboration. According to the data, the two nations with the strongest international ties are Greece and the United States. Beyond just increasing publication numbers, international collaboration promotes the sharing of knowledge, resources, and ideas, which eventually results in higher-caliber research outputs. The global character of research in orthodontic alloys and corrosion is highlighted by the VOSviewer analysis, which also highlights the strong collaboration ties between these top nations and institutions. Cross-border research relationships are crucial for promoting innovation and discovery in this field, as demonstrated by the collaboration between the National and Kapodistrian University of Athens and other European institutions. Thus, even though China, India, and Brazil lead the world in publications, the true strength of the research community is found in cross-national collaborations that facilitate knowledge sharing and advance our understanding of orthodontic alloys and corrosion worldwide.

Leading Author

Table 4 showed the top 10 Author in orthodontic corrosion and alloy research. These authors are associated with many institutions across the world, including as China, India, Switzerland, Croatia, Italy, and Romania. This table demonstrates a wide range of academic contributions that demonstrate the interest in this field of study around the world. The list is leads by Rajendran Susai Santhammal of St. Antony’s College of Arts and Sciences for Women in India, who has an impressive record of 2,647 total citations, an h-index of 27, and 233 publications since 1991. With Rajendran in the vanguard, this substantial contribution highlights the crucial role India plays in orthodontic corrosion research. His long history of publications indicates his dedication to furthering this field’s research. Theodore Eliades of Universität Zürich, Switzerland, is a notable figure in the field of research after Rajendran. He has a significant effect, as evidenced by his impressive h-index of 50, 361 publications, and 8,779 citations. Eliades’ work has been essential in understanding the complex behaviors of orthodontic materials, which has influenced research in academia and real-world applications. The third most prolific author is Javier Gil of Universitat Politècnica de Catalunya in Spain, with 190 publications, an h-index of 44, and 5,783 citations overall. Thanks to Gil’s achievements, Spain is well-represented in the field of orthodontic corrosion research. Spanish academics are known for their broad collaboration and interdisciplinary approaches.

Additional noteworthy contributors include Luigi Calabrese from the Università degli Studi di Messina in Italy and Singh Gurmeet K. from the Delhi Technological University in India. Their substantial scholarly contributions are demonstrated by their high citation metrics and publication counts. While Calabrese claims 213 publications with an h-index of 39, Singh has 202 publications with an h-index of 41. In the field of orthodontics, both writers have made a substantial contribution to our knowledge of alloy behavior and corrosion processes. Anitha Nilavan, a budding star in the field, hails from St. Antony’s College of Arts and Sciences for Women in India. Since making her debut in 2022, she has contributed to 15 articles, accumulating an h-index of 1, and increasing her citation count to 9. Anitha’s latest contributions are indicative of an increasing number of young Indian academics who are expected to carry on the nation’s orthodontic research tradition.

Author Keywords

In the present bibliometric study, we are attracted to Orthodontic corrosion and alloy while seeking author keyword co-occurrence. The analysis process was optimized by generating a thesaurus file to group synonymous words in one accurate sentence. Figure 2 is a graphical representation of the author’s keyword analysis over ten years (2014–2023). The study presents a comprehensive set of 2866 keywords. Among these, 28 terms met the criterion of appearing at least five times in VOSviewer’s dataset, which is a sizable collection. The size of a bubble in this visual representation shows two things: how often the keyword is consumed and to what extent it connects with other keywords. The study revealed that the word most often mentioned was ‘corrosion,’ which was mentioned 109 times. Orthodontic correction and alloy category exhibited a notable frequency of 109 occurrences, closely following the previous category. The significance of orthodontic correspondence in this field is highlighted, emphasizing its essentiality as a crucial component in contemporary sample preparation methodologies.

Terminology and Concept

According to the data presented in Fig. 5, the keyword “corrosion” was observed with the highest frequency, appearing a total of 109 times and generating 44 connections with other keywords. Notably, it demonstrated the broadest range in relevance compared to different keywords. Furthermore, general terms such as “biocompatibility” were frequently used, appearing 29 times with 26 connections, emphasizing their alignment with the core focus of this research. The author’s keywords, closely tied to the study’s objectives, are reflected in Table 1, which includes publications centered on orthodontic alloys and corrosion-related phenomena. Various author keywords frequently associated with orthodontic alloys and their properties included “orthodontic wire” (32 occurrences, 19 links), “corrosion resistance” (31 occurrences, 21 links), “fluoride” (22 occurrences, 20 links), “stainless steel” (22 occurrences, 21 links), and “orthodontic” (17 occurrences, 17 links). These terms highlight the significant focus on material performance, biocompatibility, and the interaction of orthodontic alloys with environmental factors.

Author keywords: A total of 2866 author keywords were recorded, among which 4466 (73.7%) were used only once, 732 keywords (12.1%) were used twice, and 261 (4.3%) were used thrice. After re-labeling synonymous single words and congeneric phrases, 401 keywords met the threshold of a minimum of 5 occurrences for the mapping in VOSviewer. Our results showed that corrosion was the most frequently encoutered keyword with 109 occurrences and 44 links to other keywords (Fig. 5). Biocompatability the second occurrences among with 29 and 26 links, another kerwords orthodontic wire accuraned 32 with 19 linked, Corrosion resistance (31 occurrences,21 links) Flourid (22 occurrences, 20 links) Stainless steel (22 occurrences, 21 links), orthodontic (17 occurrences, 17 links)Our findings indicated that “corrosion” was the most commonly encountered keyword, appearing 109 times and linked to 44 other phrases (Fig. 5). Biocompatibility ranked second with 29 and 26 links. In contrast, the keyword orthodontic wire appeared 32 times with 19 associated links. Corrosion resistance (31 instances, 21 connections), Flourid (22 cases, 20 connections), Stainless steel (22 instances, 21 connections), orthodontic (17 cases, 17 connections). This bibliometric study examines microextraction techniques and drug analysis, specifically analyzing the co-occurrence of author keywords. The analytical approach was optimized by developing a thesaurus file that consolidated synonymous terms into a singular, complete phrase. As illustrated in Figure 2, the author’s keyword analysis spans a decade, from 2014 to 2023. The analysis includes a total of 3647 keywords. A specific selection of 28 keywords appeared in VOSviewer’s dataset at least five times. The image uses bubble size to illustrate two critical attributes: the frequency of a keyword’s occurrence and the extent of its associations with other keywords. The analysis revealed that the most frequently cited keyword, occurring 122 times, was “sample preparation techniques.” The category of “microextraction techniques” demonstrated a significant frequency of 105 occurrences, closely behind the preceding category. The importance of sample preparation and microextraction techniques in this domain is underscored, affirming their necessity as vital elements in modern sample preparation methodology. These techniques offer substantial benefits in improving time efficiency, reducing solvent consumption, achieving cost-effectiveness, and accurately detecting trace analytes in complex sample matrices that often comprise high molecular weight compounds. According to the data presented in Fig. 3, the keyword ‘sample preparation techniques’ was observed with the highest frequency, occurring a total of 122 times and generating 119 connections with other keywords. Notably, it demonstrated the broadest range in size compared to all other author keywords.

Furthermore, it was discovered that there is widespread use of more general keywords such as ‘microextraction techniques’, with a total of 105 occurrences and 92 links. The author’s keywords are of significance as they are closely aligned with the primary objective of this research, as evident from the exclusive inclusion of publications in Table 1 that focus on the application of microextraction techniques in sample preparation. Various author keywords were frequently used in discussions about microextraction techniques and drug research. These keywords encompassed terms such as ‘solid-phase microextraction’ (92 occurrences, 55 links), ‘high-performance liquid chromatography’ (57 occurrences, 50 links), ‘green chemistry’ (34 occurrences, 41 links), and ‘dispersive liquid-liquid microextraction’ (74 occurrences, 51 links).

Topic of Interest

This bibliometric report focuses on the noteworthy contributions and new research directions in the subject of orthodontic alloys and corrosion. The longevity, safety, and effectiveness of orthodontic devices are directly impacted by this field of study, making it essential to the development of dental materials and their uses in orthodontics. Our goal is to provide a comprehensive overview of the significant advancements and approaches in this subject by examining publications from a range of scholarly journals. To influence the conversation surrounding the corrosion resistance of orthodontic alloys, our study highlights the key research areas, prominent contributors, and relevant journals. We also want to draw attention to the interdisciplinary character of this field of study, which combines knowledge from engineering, chemistry, materials science, and dentistry. Ultimately, the results of this study will provide a valuable tool for practitioners and academics interested in optimizing orthodontic materials, thereby supporting improved clinical outcomes and innovation in dental practice.

Limitations of the Study

Since our search was limited to specific terms, such as “orthodontic alloy” and “corrosion,” within titles and abstracts on the Scopus database, the scope of this study may not encompass all studies on orthodontic alloys and corrosion available in the scientific literature. This restriction may have resulted in the exclusion of pertinent research published in less prestigious publications or using alternative terminologies²⁵. To ensure a more thorough analysis, it is advised that future research compare and assess multiple databases, including Scopus, Web of Science, and PubMed. For instance, the Web of Science has elements that Scopus does not, such as “Hot Papers,” which highlights recently released papers that have garnered significant attention and citations. Thorough bibliometric analyses can be produced by utilizing a variety of data sources. Since our search was limited to specific terms, such as “orthodontic alloy” and “corrosion,” within titles and abstracts on the Scopus database, the scope of this study may not encompass all studies on orthodontic alloys and corrosion available in the scientific literature. This restriction may have led to the exclusion of pertinent research published in less prestigious publications or using alternative terminology. To ensure a more thorough analysis, it is advised that future research compare and assess multiple databases, including Scopus, Web of Science, and PubMed. For instance, the Web of Science has elements that Scopus does not, such as “Hot Papers,” which highlights recently released papers that have garnered significant attention and citations. Thorough bibliometric analyses can be produced by utilizing a variety of data sources. It is essential to acknowledge that the bibliometric approach may have inherent biases, such as an overreliance on citation measures and a propensity to overlook groundbreaking but less-cited work, despite providing valuable insights into the body of literature. Subsequent investigations should delve into the development of innovative analytical instruments and approaches that can precisely track research patterns and changes in orthodontic alloys and corrosion. Additionally, the VOSviewer program was the primary analytical tool used in this study. Using additional bibliometric techniques in subsequent investigations could enhance the depth and understanding of the inquiry into orthodontic alloys and corrosion.

Conclusion

Drawing on 710 papers from the Scopus database, this bibliometric study provides a comprehensive overview of advancements in orthodontic alloys and corrosion research. The field has grown significantly over the last five years, indicating a positive trend that is likely to continue in the years to come. According to our data, there are numerous publications and strong international partnerships, particularly among powerful nations such as China, India, and the US. These countries have been major actors in the advancement of orthodontic alloys and corrosion research, frequently collaborating with scientists from other regions, such as Greece and Croatia, to expand the body of knowledge in the field. Our analysis focuses on several well-established areas of the field’s research, including the material characteristics, corrosion resistance, and biocompatibility of orthodontic alloys.

Additionally, we identified new areas of interest that could be explored in the future, such as the application of nanotechnology in alloy development and innovative corrosion prevention methods. These emerging subjects may serve as primary themes for future research, offering fresh perspectives and new developments in the field of orthodontic material science. The increasing interest in corrosion and orthodontic alloys underscores the need for ongoing research and interdisciplinary collaboration. Through establishing collaborations and investigating novel subjects, the scientific community can enhance our comprehension and optimize the effectiveness and security of orthodontic materials. To spur innovation and improve clinical outcomes in orthodontics, future research initiatives should leverage existing trends and emerging prospects.