Association between the inclination of the lateral incisors and the position of the erupting canines on panoramic radiographs

OBJECTIVE. To analyze correlations between the inclination of the permanent maxillary lateral incisors and the intraosseous position of the erupting permanent maxillary canines on panoramic radiographs. MATERIAL AND METHODS. The inclination of the lateral incisor to the midline, the mesiodistal position of the crown of the canine, and the inclination of the canine to the midline and to the long axis of the adjacent incisor were measured on panoramic radiographs of 1013 subjects aged 8-11 years. RESULTS. The distal inclination of the lateral incisor crown increased until 10 years, after which no significant changes occurred. The canine erupted with increasing mesial inclination of the crown until 9 years, after which it began to progressively right itself. As a result, inclination of the canine to the adjacent incisor increased between 8 and 9 years and decreased between 10 and 11 years. Until the children reached 9 years of age, the more mesial the crown of the unerupted canine, the greater the decrease in the distal inclination of the lateral incisor crown. CONCLUSIONS. The inclination of the crown of the lateral incisor varies during eruption of the canine, increasing distally until 10 years as a physiological stage in the mixed dentition. The inclination of the lateral incisor is also associated with the mesiodistal position of the canine crown. The mesial intraosseous location of the canine crown results in righting of the lateral incisor.