Mandibular Advancement Devices for Obstructive Sleep Apnea: Bibliometric Analysis (1984–2024)

Introduction

Obstructive Sleep Apnea (OSA) is the most common sleep breathing disorder, characterized by disruption to the normal ventilation during sleep due to complete or partial upper airway obstruction.¹ This obstruction leads to interrupted breathing, decrease in oxygen levels, and poor sleep quality, which often results in morning headaches and increased daytime sleepiness associated with feeling of tiredness and fatigue during the day.^2–4 Estimates suggest that OSA affects between 9% to 38% of adults, with a higher risk in men, older individuals, and those with a higher body mass index.^5,6 If left untreated, OSA can lead to serious health consequences such as cardiovascular diseases, metabolic disorders, and impaired cognitive function.^7,8 Notably, OSA is a well-established risk factor for elevated blood pressure and the development of coronary artery disease, with mechanisms involving sympathetic activation, oxidative stress, and endothelial dysfunction, which contribute to increased cardiovascular morbidity and mortality.^9–12

The gold standard treatment for OSA is Continuous Positive Airway Pressure (CPAP).^13,14 It is highly effective because it keeps the airway open by pushing a steady flow of air through a mask.¹³ This helps patients breathe normally during sleep and improves their sleep quality.¹⁴ The main limitation with CPAP is patients’ acceptance and compliance.^2,15 Studies differ in the reported compliance with CPAP, but it can range from 40 to 60% who are using CPAP more than 4 hours per night after 6 months.^16–18 Reported barriers to patients’ compliance include discomfort, noise, or difficulty wearing the mask.^19,20

For patients who are CPAP intolerant, Mandibular Advancement Devices (MADs) have become a recommended option, especially in cases of mild to moderate OSA.²¹ MADs works by holding the lower jaw slightly forward during sleep, which helps prevent the airway from collapsing.^22,23 Studies have shown that MADs can reduce the Apnea Hypopnea Inde (AHI), improve oxygen levels, and improve sleep quality.^24,25 Custom-made MADs are superior in treatment outcomes compared to ready-made appliances, due to improved fitting and comfort.^26,27 However, prolonged use may cause minor dental changes, requiring regular follow-up.^28,29

In recent years, the use of MADs has grown alongside increased educational efforts and support for their implementation, particularly through initiatives by the American Academy of Dental Sleep Medicine.³⁰ Programs such as the Mastery Courses and the Qualified Dentist designation have contributed to the wider adoption of MADs and stimulated further research in this field.^31,32 Despite the growing number of studies and systematic reviews focusing on clinical efficacy, there remains a lack of comprehensive bibliometric analysis. Such an analysis is essential to evaluate publication trends, citation impact, collaboration networks, and emerging topics, while also identifying key contributors and research gaps. Hence, the aim of this study was to conduct a bibliometric analysis of the scientific literature on mandibular advancement devices for obstructive sleep apnea, highlighting key trends, influential publications, collaboration patterns, research gaps, and potential future directions.

Materials and Methods

This study employed bibliometric analysis to provide an overview of the scientific landscape, highlighting the contributions of countries, organizations, and researchers to scholarly publication production. Choosing the right indexing database is crucial for bibliometric research. The literature indicates that the Web of Science (WoS) database, being the oldest and largest, covers publications from numerous high-impact journals.^33,34 Therefore, the WoS database from Clarivate Analytics was selected to gather the data necessary to achieve the objectives of this study. The decision to rely exclusively on Web of Science was based on its rigorous journal selection process, structured metadata, and advanced citation analysis capabilities, which make it the benchmark database for bibliometric research. This ensured consistency and reliability in data retrieval and citation tracking. The following query was entered using the Advanced Search option, with the Topic selection applied.

“Mandibular Advancement Device” OR “Mandibular Advancement Devices” OR “Mandibular Advancement Appliance” OR “Mandibular Advancement Appliances” OR “Mandibular Advancement Splint” OR “Mandibular Advancement Splints” OR “Mandibular Repositioning Appliance” OR “Mandibular Repositioning Appliances” OR “Mandibular Repositioning Device” OR “Mandibular Repositioning Devices” OR “Mandibular Repositioning Splint” OR “Mandibular Repositioning Splints” OR “Oral Appliance” OR “Oral Appliances”.

We retrieved data from the Web of Science (WoS) database using the “Topic” field, with data collected on May 12, 2025. The time span for the data ranged from the earliest publication on the selected topic in 1984 to December 31^st, 2024. A total of 2,687 published documents were initially retrieved. After applying exclusion criteria, 2,610 documents were included in the analysis (Figure 1). Documents excluded were records from 2025, letters, early reviews, corrections, notes, news items, reprints, and retracted publications. The results were extracted and analyzed using VOSviewer and MS Excel software. VOSviewer software was used to identify the most frequent keywords in the dataset. In bibliometric analysis, occurrence refers to how often a specific keyword appears across the analyzed documents, reflecting its frequency and prominence within the dataset. Additionally, Total Link Strength is an important metric that measures the level of connection or co-occurrence between keywords, offering insights into the relationships and interactions between terms in the dataset.

Figure 1 The flowchart illustrates the process of selecting documents for bibliometric analysis.

Results

A total of 2,610 documents were selected for bibliometric analysis. The vast majority were published in English (n = 2,508; 96%), while 4% (n = 102) were published in eight other languages, including French, German, Italian, Japanese, Turkish, Korean, Portuguese, and Spanish.

Periodic Growth in Publication

Of the 2,610 documents included in this analysis, 91% were published in the last 20 years. Notably, about two-third of the documents (62%) were published in the last decade. These documents have collectively received 59,930 citations, with an average of 22.96 citations per document. The highest citation peak occurred for documents published in 2009 as illustrated in Figure 2.

Figure 2 Annual publication output and citation trends (1984–2024). The blue bars represent the number of publications per year, while the Orange line indicates the corresponding annual citations. Data were retrieved from the Web of Science database and analyzed by the authors.

Frequently Used Sources of Publications

The selected 2,610 documents were published in 598 sources of publications and more than half of sources (n=339; 56.68%) had published a single document each, whereas 43% (n=1,113) of the documents were published in top 15 most frequently used sources of publications mentioned in Table 1. “Sleep and Breathing” journal has the highest number of papers (n=161), followed by “Sleep”, “Sleep Medicine” and “Journal of Clinical Sleep Medicine” with 156, 120 and 105 papers, respectively. “Chest” journal also stands out with a high citation impact of 57.74, despite having fewer documents (n=58) compared to some of the other sources. “Sleep Medicine Reviews” journal has a high citation impact (56.54) and a moderate number of documents (n=37). Overall, “Journal of Clinical Sleep Medicine” has the higher citation impact (50.54), meaning its articles are cited on average 50.54 times.

Table 1 Top 15 Journals Publishing on Mandibular Advancement Devices for OSA

Top 15 Countries

A total of 81 countries contributed to the 2,610 documents, with the details of the top 15 countries based on the number of documents shown in Table 2. The United States leads both in the total number of documents published (n=641) and citations (n=21,584), with a relatively high citation impact of 33.67. Canada (31.92 citation impact) and Belgium (33.46 citation impact) also exhibit strong citation impacts, indicating that their research is influential despite publishing a moderate number of documents (265 and 135, respectively). The Netherlands produces research with the highest citation impact, followed by Australia and the United States. India, on the other hand, has the lowest citation impact among the top 15 countries, while it contributes a significant amount of research (n=87).

Table 2 Leading Countries by Publication Volume and Citation Impact in MAD-OSA Literature

Top 15 Research Producing Organizations

A total of 2,853 organizations were identified using VOSviewer software, with more than two-thirds (n=1,950; 68.34%) contributing a single document. The citation details and impact of the top 15 most productive organizations are outlined in Table 3. The University of Sydney leads in document count (n=138) but has a lower citation impact of 28.11. In contrast, Harvard University, despite ranking 10^th in document count (n=56), stands out with the highest citation impact at 102.32. The University of British Columbia demonstrated both a high publication output (n=111) and a strong citation impact (37.56), highlighting its influential role in the field.

Table 3 Leading Organizations by Research Output and Citation Impact in MAD-OSA Literature

Top 15 Productive Authors, Authorship Pattern, and Most Frequent Keywords

A total of 8,922 distinct authors were identified by VOSviewer software, with the majority (n=7,040; 78.90%) contributing to only a single document. Table 4 lists the top 15 most prolific authors. Cistulli, Peter A. stands out as the leading author in terms of citation impact, achieving a score of 73.56 across 106 publications, indicating a consistently high influence in the field. Marklund, Marie follows closely with a citation impact of 72.24 from 29 documents, highlighting strong impact despite a smaller output. Lowe, Alan A. has contributed to 47 documents and gained a citation impact of 53.44, which is notably high for his publication count. Figure 3 illustrate various authorship patterns, along with corresponding analyses of publication counts, citations, and citation impact. The analysis of authorship trends over three distinct time periods reveals a steady increase in the average number of authors per article, reflecting a broader shift toward collaborative research. From 1984 to 2000, the average number of authors per article was 3.73, which increased to 4.34 between 2001 and 2012, and then to 5.77 between 2013–2024. The top 30 keywords with occurrence rate of minimum of 33 times has been selected for analysis (Table 5 and Figure 4).

Table 4 Key Author Contributions to Scientific Literature on MADs for Obstructive Sleep Apnea

Table 5 Most Commonly Used Keywords in Mandibular Advancement Device Research for OSA

Figure 3 Authorship patterns and citation trends. The blue bars represent the number of publications by different authorship groups (from single-author to more than ten authors), while the Orange line indicates the corresponding total citations. Data were retrieved from the Web of Science database and analyzed by the authors.

Figure 4 Keyword co-occurrence network of publications on obstructive sleep apnea. The map was generated using VOSviewer software from the authors’ dataset retrieved from the Web of Science database. Node size represents the frequency of keyword occurrence, node color indicates cluster grouping, and the thickness of connecting lines reflects the strength of co-occurrence links.

Discussion

In recent years, Dental Sleep Medicine has drawn increased attention, especially over the last 20 years. Data from Google Trends^® shows that interest in mandibular advancement devices has grown dramatically as searches for “oral appliances for sleep apnea” have gone up by over 200% from 2016 to 2024.³⁵ This growing awareness highlights how valuable these devices have become in managing obstructive sleep apnea. Beyond public interest, researchers have published extensively on mandibular advancement devices. This study explores that scientific output through a bibliometric analysis, aiming to identify key trends, influential studies, collaboration networks, gaps in the research, and areas worth exploring in the future.

The findings of this bibliometric analysis have important implications for clinical practice and research in sleep medicine. The rapid growth of publications on mandibular advancement devices (MADs) in the last decade potentially reflects their increasing acceptance as an evidence-based treatment for mild to moderate OSA, particularly for patients who are intolerant to CPAP therapy. However, there were different terms used for these devices. The keyword analysis showed presence of semantically similar terms (eg, “Mandibular Advancement Device” “Oral Appliance” “Mandibular Advancement Splint”), which reveals a need for standardized terminology to enhance research visibility and consistency. In terms of research gaps, the bibliometric analysis on the co-occuring keywords support the need for further studies on the quality of life, temporomandibular disorders in relation to use of MADs, device optimization, and management of comorbid dental sleep disorders.^36–38 There is also a need for integrating dental sleep medicine into dental education and supporting interdisciplinary collaboration to improve patient outcomes.^39–41

The bibliometric analysis of 2,610 documents published from 1984 to 2024 reveals important trends in both research output and citation patterns. While just 9% of the documents were published in the first 21 years, the volume of publications has increased in the last two decades, with 91% of the documents appearing in the most recent 20 years. Notably, about two-thirds of these publications (62%) were published in the past decade (2015–2024), highlighting a period of rapid growth and increased research activity.

These 2,610 documents collectively garnered 59,930 citations, with an average of 22.96 citations per document, reflecting significant scholarly interest. The highest citation peak occurred in 2009, with documents from that year receiving an average of 59.66 citations, suggesting a pivotal moment or breakthrough in the field. This is mainly due to the publication of the AASM’s comprehensive clinical guideline, which accounted for 47% of the citations in documents published in 2009 and provided evidence-based recommendations on the evaluation, management, and use of oral appliances for obstructive sleep apnea.¹⁴ In summary, the analysis reveals substantial growth in the field, particularly in recent years, with the 2009 publications standing out as especially impactful.

The analysis of top 15 frequently used journals highlighted that more of documents published in journals related to sleep, respiratory, and orthodontic research fields and their citation impacts varying considerably. Journals like “Journal of Clinical Sleep Medicine” and “Chest” stand out with high citation impacts, while others like “Journal of Sleep Research” have a lower citation impact despite publishing a moderate number of documents. The overall distribution indicates which journals are more influential within their respective fields based on how frequently their articles are cited.

The main limitation of this study is that the analysis relied solely on the Web of Science database, which, although considered the benchmark for bibliometric research, may introduce database bias. Future researchers can include other databases such as Scopus or PubMed, as this will provide broader coverage for the literature on MADs. Additionally, future studies could utilize advanced bibliometric techniques, such as field-normalized citation metrics or regression analysis. These techniques can help to explore the relationships between collaboration networks and citation impact.

Conclusion

• This bibliometric analysis covers research on mandibular advancement devices (MADs) for obstructive sleep apnea (OSA) from 1984 to 2024.
• There has been a sharp increase in publications over the past two decades, reflecting growing interest in MADs as an alternative treatment for OSA.
• The United States produced the highest number of publications, followed by Canada and Australia.
• The Netherlands and Sweden had a higher citation impact, suggesting more influential research despite fewer publications.
• The top contributing institutions were:
  • The University of Sydney, Australia
  • University of Antwerp, Belgium
  • The University of British Columbia, Canada
• Peter A. Cistulli was the leading author in terms of citation impact, with:
  • 106 publications
  • A citation score of 73.56