Ectopic Eruption And Canine Path

To investigate the correlation between ectopic eruption of the first permanent maxillary molars and the eruption path of the permanent canines in children aged 6 to 9 years. Panoramic radiographs of children with ectopic eruption of the first permanent maxillary molars were analyzed. Measurements included the inclination angle of the permanent canines, eruption height, and position relative to adjacent teeth (S1: distal to the deciduous canine; S2: mesial to the deciduous canine; S3: mesial to the permanent lateral incisor; S4: mesial to the permanent central incisor). Correlations were assessed. At Nolla stage 6, the severity of ectopic eruption was positively correlated with the inclination angle of the ipsilateral permanent canines (rs = 0.146, P < 0.05) but not with eruption height or position relative to adjacent teeth (P > 0.05). At Nolla stages 7 and 8, severity was positively correlated with eruption height and position relative to adjacent teeth (0 < rs < 0.7, P < 0.05) but not with inclination angle (P > 0.05). Ectopic eruption of maxillary molars may affect canine eruption due to space deficiency and genetic factors. The severity of ectopic eruption correlates with the tendency of canine impaction. Early intervention, such as deciduous canine extraction and arch expansion, may help guide proper eruption.