Tulegenova, IndiraHatipoglu, OmerTaha, NessrinMakahleh, NisreinFernandez-Grisales, RafaelBekjanova, OlgaRahimi, Mehdi;Donnermeyer, DavidMadfa, Ahmed A.Petridis, XenosIntriago, Martha GallegosShah, TanviAllawi, SafaaIvica, AnjaLim, Wen YiHamouda, AbdelrahmanJagtap, RohanMartin-Biedma, BenjaminLehmann, Anna PaulinaAlfirjani, SuhaPalma, Paulo J.Buchanan, Glynn Dale2025-09-122025-09-122025-06Pertek Hatipoğlu, F., Magat, G., Karobari, M.I. et al. Root and canal configurations of maxillary first premolars in 22 countries using two classification systems: a multinational cross-sectional study. Scientific Reports 15, 19290 (2025). https://doi.org/10.1038/s41598-025-02669-6.2045-2322 (online)10.1038/s41598-025-02669-6http://hdl.handle.net/2263/104309DATA AVAILABILITY : The datasets generated and/or analyzed during the current study are not publicly available considering that we have not required consents to publish this data, but are available from the corresponding author on reasonable request.Please read abstract in the article.en© The Author(s) 2025. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License.Maxillary first premolars (M1Ps)Cone-beam computed tomography (CBCT)Maxillary premolar teethRoot canal morphologyVertucci classificationAhmed classificationArticle