Aim: To conduct a bibliographic analysis of the research studies published in Endodontics using micro‐computed tomography (micro‐CT) as an analytical tool over a 25‐year period.Methodology: The Web of Science electronic database was accessed, and an advanced search using strict criteria was undertaken from January 1995 to June 2020 for studies in the field of Endodontics that used micro‐CT as an analytical tool. A further search was conducted between January and August of 2020 for a combination of specific terms and descriptors. For each selected article, the following parameters were recorded: field of the study, analysed specimen, publication title and year, authorship, journal of publication, institution and country of origin, collaborating institutions and countries, and number of citations. The acquired data were analysed using descriptive statistics and graphical mappings.Results: The screening process identified 877 relevant articles that were classified into 30 thematic categories. The main fields of research were root canal preparation (23.8%), root canal anatomy (17.4%), canal filling (9.2%) and root canal retreatment (7.0%). The most productive half‐decade comprised the period of 2015–2019 (n = 513; 58.5%), with the highest number of articles published in 2019 (n = 146; 16.6%). The authors who lead the list as first authors were G De‐Deus, A Keleş, F Paqué, MA Versiani and Y Gu, respectively, whilst Versiani was the most productive (n = 51). The leading countries regarding the number of studies were Brazil, China and Turkey with 236, 130 and 65 publications, respectively. The University of São Paulo (n = 90; 10.3%) followed by Wuhan University (n = 37; 4.2%) and the University of Zurich (n = 18; 2.1%) were the prominent contributors by producing the largest number of articles, whilst the University of Zurich was the most‐cited institution. The selected studies were published in 140 scientific journals, but the Journal of Endodontics and International Endodontic Journal accounted for almost 50% of the publications.Conclusion: This bibliometric analysis portrayed an original and comprehensive view on the progress and trends of the use of micro‐CT technology in endodontic research, and enabled a deep understanding of the development process in this field over the last 25 years.

The physiological processes of most living organisms follow a rhythmic pattern, which is controlled by the interaction between environmental cues and the internal circadian timing system. Different regulatory circadian genes are expressed in most cells and tissues, and disruptions in the sleep–wake cycle affect these genes, which may result in metabolic disorders and cause alterations of the immune system. The manifestations of these disrupted genes are evident in inflammatory conditions such as periodontitis and some viral diseases, including COVID-19. The brain and muscle ARNT-like protein-1 (Bmal1), an important circadian regulatory gene, decreases when the sleep–wake cycle is disrupted. Circadian genes have been linked to different events, including cytokine storm in inflammatory conditions and virus invasion. The evaluation of the effects of these regulatory circadian genes, especially Bmal1, in periodontitis and viral infection suggests that both diseases may have a common pathogenesis via the NF-κB pathway. This brief review highlights the role and importance of the circadian clock gene Bmal1 in the disease process of periodontitis and suggests its role and importance in viral infections, including COVID-19.