This is the fourth volume of Universitas Odontologica with the current periodicity. From 2020, the journal is being published by rolling volume and not by issue. Any article received (that meets the initial style and methodology requirements) will be refereed by peers external to the institution where the authors are affiliated and, if accepted, the necessary corrections will be completed, submitted to a style review, and published immediately. Volume 42 includes, in addition to articles in our regular sections, two thematic dossiers, one on "Research Incubators in Dentistry" and another on "Temporomandibular disorders, orofacial pain, bruxism and sleep apnea."