Treatment planning for maxillary canine displacement based on individula skeletal maturity

AIM: In treatment planning for a palatally displaced canine it is important to determine the timing of potential eruption of the canine (when interceptive procedures can be attempted) versus impaction of the tooth. Thus the aim of this study was to assess the relationship between the eruption of the permanent maxillary canine and individual skeletal maturity in subjects with different skeletal relationships in the sagittal and vertical planes. SUBJECTS AND METHOD: One hundred and fifty two subjects (63 males, 89 females) with erupting permanent maxillary canines. The individual stage of cervical vertebral maturation (CVM) was assessed on lateral cephalograms. Following this analysis, the subjects were divided into pre-peak (before the pubertal growth spurt, CS1 and CS2), peak (during the pubertal growth spurt, CS3 and CS4), and post-peak (after the pubertal growth spurt, CS5 and CS6) groups. Skeletal relationships in the sagittal and vertical planes were evaluated, and relationships to timing of canine eruption were statistically tested. RESULTS: The pre-peak group comprised 86 subjects, the peak group 66 subjects. No subjects were classified as post-peak. The differences in prevalence rates between the pre-peak and peak groups were statistically significant (P < 0.001). The prevalence rate for hyperdivergent subjects showing eruption of the permanent maxillary canine in the pre-peak group (37.2%) was significantly higher than in the reference orthodontic population (21%). CONCLUSION: Eruption of the permanent maxillary canine can occur at any stage during skeletal maturation before the end the pubertal growth spurt (CS1 through to CS4), with hyperdivergent subjects showing more frequently pre-pubertal canine eruption.