Martín-Romanillos, EugeniaFeijoo García, GonzaloMartín-Vacas, AndreaMourelle Martínez, RosaGallardo López, Nuria EstherCaleya Zambrano, Antonia María2026-01-252026-01-252025-03-29Martin-Romanillos E, Feijóo G, Martín-Vacas A, Mourelle-Martínez MR, Gallardo-López NE, Caleya AM. Analysis of the Relationship Between Unilateral Posterior Crossbite and Alterations in the Eruptive Trajectory of Maxillary Canines, the Occlusal Plane, and the Inclination of the Labial Commissure. Children (Basel). 2025 Mar 29;12(4):437. doi: 10.3390/children1204043710.3390/children12040437https://hdl.handle.net/20.500.14352/130912Objectives: The aim was to establish whether there is a relationship between the presence of unilateral posterior crossbite (u-PCB) and the mesio-distal inclination of permanent upper canines, the angulation of the occlusal plane, or the labial commissure inclination in children. Methods: A cross-sectional association study was conducted. Panoramic radiography was used to measure the inclination of the canines and the occlusal plane, and frontal rest photography was used to measure the inclination of the labial commissure. The measurements were performed with tpsDig264 software version 2.25, 2016, Ecology & Evolution, SUNY), and the data obtained were analyzed with SPSS 22.0 software, using ANOVA and Kruskal-Wallis tests for the statistical analysis. Results: A total of 106 patients with u-PCB and 41 patients in the control group were studied. No statistically significant differences were observed in the inclination of the right and left canines in patients with u-PCB compared to patients in the control group. There is a relationship between the presence of u-PCB and the inclination of the occlusal plane. No statistically significant differences were observed in the inclination of the labial commissure in patients with u-PCB compared to patients in the control group. Conclusions: There is no relationship between the presence of u-PCB and the alteration in the eruptive trajectory of the permanent upper canines or in the inclination of the labial commissure. However, a relationship between the presence of u-PCB and altered occlusal plane inclination was found.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/journal article2227-9067https://doi.org/10.3390/children1204043740310058https://www.mdpi.com/2227-9067/12/4/437https://pubmed.ncbi.nlm.nih.gov/40310058/open access616.314.2:612.31CaninesCrossbiteLabial commissureOcclusal planeOrthodonticsOdontología infantilOclusión dentalOrtodoncia3213.13 Ortodoncia-Estomatología2410.02 Anatomía Humana2410.04 Desarrollo Humano