Age and Gender Differences in Maxillary Canine Impaction Severity and Orthodontic Treatment Difficulty – A Retrospective Cross-Sectional Study

Objectives: The objectives of this study were to compare the maxillary canine impaction severity and orthodontic treatment difficulty in relation to age and gender. Material and Methods: Orthopantomograms of 105 patients with maxillary canine impaction were retrospectively collected and divided into 50 adolescents (11–17 years; 30% females) and 55 young adults (18–25 years; 34% females). Canine impaction severity was determined using one angular and three linear radiographic measurements, while orthodontic treatment difficulty was determined using a modified Pitt et al. index. Age and gender differences were assessed using Chi-square with Bonferroni correction and Mann–Whitney U-tests (P < 0.05), while the association between orthodontic treatment difficulty index score and age was assessed using linear regression analysis (95% confidence interval). Results: Compared to young adults, adolescents had mild (<30°) canine long axis to midline angulation (P = 0.008) and distally positioned cusp tip of impacted canine relative to adjacent lateral incisor root (P < 0.001). Meanwhile, males compared to females had distally positioned cusp tip of impacted canine relative to adjacent lateral incisor root (P = 0.008), while females compared to males had the canine cusp tip mesial to lateral incisor root (P = 0.002). The orthodontic treatment difficulty trend increased with age (R2 = 0.077; P < 001) and was higher in young adults than adolescents (P = 0.0218). Conclusion: The severity of maxillary canine impaction was higher in young adults and, to a lesser extent, in females. Orthodontic treatment difficulty of impacted maxillary canines also increased with age but not gender.