This study assessed the features of the 100 most-cited papers on diabetes mellitus (DM) in dentistry using bibliometric measures. A search of the most cited papers on DM using journals included in the category "Dentistry, Oral Surgery and Medicine" in the Web of Science database up to January 2023 was performed. The complete bibliographic records of the selected papers were exported in plain text or Research Information Systems (RIS) file format. The following bibliometric indicators were collected: title, year, authors, number of citations, mean number of citations, institution, country, continent, study design, journal, impact factor, and keywords. Graphical bibliometric networks were created using the VOSviewer software. The number of citations for the 100 most-cited papers in DM research ranged from 111 to 566. Six papers each had more than 400 citations. Most were observational studies (n = 50) from the United States (USA) (n = 23) and were published in the Journal of Periodontology (30%; n=30). Robert Genco was the most cited author and contributed the most to the top 100 articles (3,653 citations; n = 13). The VOSviewer map of co-authorship showed the existence of clusters in research collaboration. The most prolific institutions were the Universities of Buffalo and Michigan (n = 6 each). "Diabetes mellitus" was the most frequent keyword, with 31 occurrences. In conclusion, the most cited studies that investigated the relationship between dentistry and DM were in periodontology. Observational studies, primarily from the USA, have been the most cited thus far.