Haptic and Force Feedback Technology in Dental Education: A Bibliometric Analysis

The haptic and force feedback technology has received an increasing attention in dental schools due to its effectiveness in psychomotor skill training. However, the bibliometric analysis on haptic and force feedback technology in dental education is still scarce. Therefore, the aim of this study was to perform a bibliometric analysis of the development of haptic and force feedback technology and its changing trends in dental education. From 1 January 2001 to 30 November 2022, all papers published on haptic and force feedback technology were searched from the Web of Science Core Collection database. These data were then entered into Apple Numbers for descriptive bibliometric analysis and visualized using VOSviewer software. A total of 85 articles were retrieved following the inclusive and exclusive criteria. The results demonstrated that USA and China exhibited the most publications. The combination of correspondence author and author co-citation analysis identified the more prominent authors in this research field. The top-cited and the average citation count per year ranking led to different views of popularity. A significant increase in the number of haptic and force feedback technology publications were found in the last two years. Virtual reality is the main keyword that indicates more new integrative applications currently underway. Taken together, this study provides a detailed bibliographic analysis of haptic and force feedback technology in dental education to indicate representative authors, literatures, keywords, and trends. These detailed data will help researchers, teachers, and dental students as a very useful information when trying to make haptic and force feedback technology more prevalent in dental education in the near further.


Introduction
Haptic and force-feedback technology allows a user to experience tactile feeling or a sense of touch when operating an instrument [1]. The force-feedback device first used in dental education was developed by the University of Iowa for the detection of caries cavities [2]. Haptic and force feedback technology was considered an add-on function of the pure-vision virtual environment that could facilitate dental students with a more real operating scenario [1]. Dental students can improve their skills in haptic and forcefeedback environments and let the skill levels be differentiated and identified [3]. The skill perception from haptic and force feedback technology can also be transferred to real operation situations [4].
Bibliometrics is a commonly used mathematical and statistical tool for the literature analysis of books, papers, or other publications. It is a systematic research analysis method for citation patterns in the literature. The quantitative evaluation was used to analyze bibliographic information including number of citations, citation density, citation ranking, and impact factor. In addition, the bibliometrics information about author such as coauthorship's country, institutional affiliation, and productivity of researchers were also evaluated. These analyses are helpful for understanding the history of academic activities, and impact factor. In addition, the bibliometrics information about author such as co-au thorship's country, institutional affiliation, and productivity of researchers were also eval uated. These analyses are helpful for understanding the history of academic activities identifying current research interests, and guiding potential future research directions [5 Bibliometric analysis has been evaluated in various fields of dentistry, oral surgery and medicine such as the characteristics of a specific journal [6,7], dental education [8], and platelet-rich fibrin [5]. Since 2001, there were several articles reported on the popularit of various haptic and force feedback technology in dental education [1,9]. As far as w know, there is still limited information about the applications, demographic distributions and the overall trend of developments about this innovative technology. Therefore, th aim of this study was to provide a bibliometric analysis of haptic and force feedback tech nology, trying to provide an overview and provide a different perspective on its applica tion in dental education.

Database and Search Strategy Selection
The Web of Science database (Clarivate Analytics, Philadelphia, PA, USA) is the old est database designed for more detailed citation analysis for researchers [10]. In this study Web of Science, with its sub-databases including Science Citation Index Expanded (SCIE and the Social Science Citation Index (SSCI), was assessed from 1 January 2001, to 30 No vember 2022. The search strategy was Topic = ("dental haptic") OR Topic= ("dental forc feedback") AND Topic = ("dental education") searched in the title and abstract sections The exclusion criteria were applied to the following conditions: (1) not focus on hap tic/force feedback technologies in dental education; (2) duplicated article; (3) a conferenc abstract. After the process of exclusion, the bibliometric data of the included reference were exported from Web of Science for further analysis. As illustrated in Figure 1, th selective strategy was according to PRISMA flow diagram [11].

Bibliometric Analysis
The extracted bibliometric data with different indexes such as number of articles, authors, affiliations, publication year, citation counts, geographical distribution, keywords, and references were exported to Numbers (Apple Inc., Cupertino, CA, USA) for the descriptive bibliometric analysis. The geographical distribution was recorded from the address of correspondence author. The VOSviewer (Visualization of Similarities Viewer, VOS) software version 1.6.18 was used in this study, which is a metric analysis tool developed by Need Jan van Eck and Ludo Waltman of the Leiden University's Centre for Science and Technology Studies in Netherland. It is a popular tool in literature metrics research to present the visualized knowledge graph of the data obtained according to the principles of literature analysis [12].

Article Types
A total of 118 articles were identified by the search strategy from the Web of Science database. A total of 33 articles were excluded for the reasons due to not focus on haptic and force feedback technologies in dental education. The most frequently published article type was original articles (n = 75), followed by review (n = 7), editorial material (n = 2), and letter to editor (n = 1). The total 85 articles within the selected criteria were listed in Table 1.  Significance of haptic and virtual reality simulation (VRS) in the dental education: a review of literature [78] Applied Sciences

71
Software testing automation of VR-based systems with haptic interfaces [79] The Computer Journal

72
The challenge of dental education after COVID-19 pandemic-present and future innovation study design [80] INQUIRY: The Journal of Health Care Organization, Provision, and Financing

73
The current situation and future prospects of simulators in dental education [81] Journal of Medical Internet Research

Authors, Affiliations, and Country
Regarding the authorship productivity, the most frequently published corresponding authors were Dang-Xiao Wang (n = 5), Siriwan Suebnukarn (n = 5), and Yu-Chao Chang (n = 3). As shown in Figure 2, the author co-citation network contributed with a minimum of ten citations of an author were illustrated by VOSviewer. Siriwan Suebnukarn ranked as the top one scholar in the author co-citation network. About the relation to the authors' affiliations were illustrated in Figure 3. From VOSviewer, the network visualization of thirteen co-authorship of affiliations published at a minimum of three articles were demonstrated. The top three affiliations were Beihang University, Thammasat University, and Peking University.
The most top publications from total 31 countries were USA (n = 18, 21%) and China (n = 18, 21%), followed by England (n = 9, 10.5%), and Thailand (n = 8, 9.4%). The coauthorship network of countries that contributed minimum three articles with overlay visualization were illustrated in Figure 4. Figure 5 displays the annual number of publication per year with the annual total citation count, the number of publication increased in recent two years. The article from Thomas et al. [2] in 2001 was the first report about haptic and force feedback technology in dental education. However, there was no publication about haptic and force feedback technology in dentistry until 2006. The highest total citation counts were found in 2011.

Citation Count
The ranking of 30 most top-cited articles is enumerated in Table 2, the characteristics of each article was recorded as followings: article title, article type, the address of correspondence author country, publication year, total citation counts, and average citations per year. The most cited article is a review article "A review of the use of simulation in dental education" [45]. The total citation number was up to 98 during past 7 years. The second most cited article is also a review article "A review of simulators with haptic devices for medical training" [1]. The total citation number was up to 96 during past 6 years. The third most cited article is an original article "Assessment of faculty perception of content validity of PerioSim©, a haptic-3D virtual reality dental training simulator" [15]. The total citation number was up to 74 during past 15 years.   The most top publications from total 31 countries were USA (n = 18, 21%) and C (n = 18, 21%), followed by England (n = 9, 10.5%), and Thailand (n = 8, 9.4%). The authorship network of countries that contributed minimum three articles with ove visualization were illustrated in Figure 4.   The most top publications from total 31 countries were USA (n = 18, 21%) (n = 18, 21%), followed by England (n = 9, 10.5%), and Thailand (n = 8, 9.4% authorship network of countries that contributed minimum three articles w visualization were illustrated in Figure 4.   Figure 5 displays the annual number of publication per year with the annual total citation count, the number of publication increased in recent two years. The article from Thomas et al. [2] in 2001 was the first report about haptic and force feedback technology in dental education. However, there was no publication about haptic and force feedback technology in dentistry until 2006. The highest total citation counts were found in 2011. The ranking of 30 most top-cited articles is enumerated in Table 2, the characteristics of each article was recorded as followings: article title, article type, the address of correspondence author country, publication year, total citation counts, and average citations per year. The most cited article is a review article "A review of the use of simulation in   Figure 5 displays the annual number of publication per year with the annual total citation count, the number of publication increased in recent two years. The article from Thomas et al. [2] in 2001 was the first report about haptic and force feedback technology in dental education. However, there was no publication about haptic and force feedback technology in dentistry until 2006. The highest total citation counts were found in 2011. The ranking of 30 most top-cited articles is enumerated in Table 2, the characteristics of each article was recorded as followings: article title, article type, the address of correspondence author country, publication year, total citation counts, and average citations per year. The most cited article is a review article "A review of the use of simulation in dental education" [45]. The total citation number was up to 98 during past 7 years. The second most cited article is also a review article "A review of simulators with haptic devices for medical training" [1]. The total citation number was up to 96 during past 6 years. The third most cited article is an original article "Assessment of faculty perception of content validity of PerioSim©, a haptic-3D virtual reality dental training simulator" [15]. The total citation number was up to 74 during past 15 years. The ranking of the top 10 most average citations per year articles is enumerated in Table 3. The most cited articles per year is an original article "The application of virtual reality and augmented reality in Oral & Maxillofacial Surgery" [66] published in 2019 with 22.67 citations/year. The second most cited articles per year is an original article "A crosssectional multicenter survey on the future of dental education in the era of COVID-19: Alternatives and implications" [73] published in 2021 with 20.00 citations/year. The third most cited articles per year is also the second most cited article shown in Table 2 "A review of simulators with haptic devices for medical training" [1] published in 2016 with 16.00 citations/year.

Keywords
As shown in Figure 6, a network visualization map of the most frequent author keywords (two or more common keywords) was illustrated by VOSviewer. Virtual reality is the subject of research shown in the yellow cluster. Dental education exhibits the main keyword in purple cluster associated with tooth drilling, COVID-19, and e-learning. The red cluster represented the haptic rendering domain. The brown cluster is studies related to the simulation of dental occlusion. In summary, virtual reality, dental education, and haptics were the top three keywords presented in this bibliometric analysis.  The results indicate the keyword trends in recent research on haptic and force feedback technology in dental education, such as COVID-19, Simodont ® , restorative dentistry, preclinical skill, haptic simulators, as well as tooth drilling, 3D printing, cephalometry, and dental occlusion.

Discussion
This study provides a constructive compilation of information on haptic and force feedback technology in dental education. It could help researchers to understand current trends, facilitate research for this technology, and even be implemented into regular dental curriculum. Virtual reality is the main keyword that accounts for the largest proportion   The results indicate the keyword trends in recent research on haptic and force feedback technology in dental education, such as COVID-19, Simodont ® , restorative dentistry, preclinical skill, haptic simulators, as well as tooth drilling, 3D printing, cephalometry, and dental occlusion.

Discussion
This study provides a constructive compilation of information on haptic and force feedback technology in dental education. It could help researchers to understand current trends, facilitate research for this technology, and even be implemented into regular dental curriculum. Virtual reality is the main keyword that accounts for the largest proportion

Discussion
This study provides a constructive compilation of information on haptic and force feedback technology in dental education. It could help researchers to understand current trends, facilitate research for this technology, and even be implemented into regular dental curriculum. Virtual reality is the main keyword that accounts for the largest proportion of this bibliometric analysis in dental education [78]. During the current COVID-19 pandemic, virtual reality simulators have led to the development and application of this technology in many dental schools [80,93]. Haptic and force feedback technology combined with a VR simulator can compensate for the limitations of traditional phantom head-based motor skill training. In addition, unlimited reproducibility, objective evaluation of preparation by computer assessment, and cost reduction were also revealed [78]. Using haptic and force-feedback technology, it could narrow down the gap between preclinical and clinical skill level [70], reduce anxiety among novice dentists, and improve patient safety [84]. In 2015, the United Nations announced the Sustainable Development Goals, which have become a common task for all dental schools over the years. Therefore, the virtual digital 3D simulator has become a new favorite because of its ability to provide high quality education, reduce inequality, and decrease waste [87].
Currently, the application of haptic and force-feedback technology in dentistry is still limited to some disciplines, such as operative dentistry, which requires the skill of tooth preparation. In terms of recent keyword trends and the average number of citations per year, it can be found that some new techniques are being integrated with haptic and force feedback technology in new devices that have the potential to become more applicable in current preclinical learning and training. Recently, some haptic and force feedback devices could not only provide pre-clinical skill training, but also equipped with customized treatment model to achieve the goal of precision medicine. For example, intraoral scanner assembled digital models from patients were successfully imported into haptic 3D virtual reality simulator for the learning of teeth preparation before clinical managements [70,84]. Moreover, virtual 3D tooth creation form patients combined with haptic and force feedback technology were implemented in endodontic learning and training [94,95]. Recently, the haptic feedback technology was initiative in oral and maxillary surgery learning for lower impaction third molar extraction [96].
The data from WoS were only used for the analysis of the first author, resulting in the omission of other outstanding authors in the same article. In addition, the clustering results show that an author can only belong to the same group, and when the author is a cross-disciplinary or multi-specialty author, the clustering results do not naturally present the author characteristics; therefore, a modified analysis method may be developed to improve this imperfection [97].
Publications on haptic and force feedback technology in dental education were retrieved from WOS and the data was analyzed objectively and comprehensively. However, there are some limitations in this study. First, only one database Web of Science was adopted. Articles written in books, or conference proceedings were not covered in Web of Science. More databases would be added to compare the differences in the future. Second, the majority of Web of Science articles are in English. Therefore, most of the non-English language articles were neglected or excluded. Third, the recent 2-year growth trends predict an increase in the number of publications on haptic and force-feedback technology in dental education published in the preprint online database were not enrolled. Finally, the number of citations might reflect the impact or influence the article. However, this method has a potential lack of in-depth analysis of each article.
Despite these limitations, we believe the data that presented in this study still provide significant insight into the scope and type of the large body of haptic and force feedback technology in dental education. The number of censored studies of haptic and force feedback technology from WOS database over the past 20 years is relatively small (n = 85), perhaps haptic and force feedback technology is still needed to improve for mimicking more clinically relevant virtual realistic simulation training environment. However, it has many benefits in pre-clinical skills learning such as motor skill development, basic manual dexterity training and even facilitate patient safety [9,60]. Further experiments are necessary to expand and prove the training effectiveness of haptic and force feedback technology [9,80]. It will take time to make this issue more popular.

Conclusions
To the best of our knowledge, this is the first study to analyze the bibliometric data of haptic and force feedback technology in dental education. According to the results of bibliometric analysis, there has been an increasing tendency toward this topic over the most recent two years. Teaching motor skill is important for dental students. It is believed that more studies will be conducted in the future to confirm the reliability and validity of haptic and force feedback technology in dental education.

Data Availability Statement:
The data presented in this study are available on request from the corresponding author.

Conflicts of Interest:
The authors declare no conflict of interest.