Difficulty of palatal impacted canine treatment in different sagittal and vertical skeletal malocclusions: A retrospective 3D evaluation.

OBJECTIVE

To evaluate the difficulty of impacted canine treatment in different kinds of sagittal and vertical malocclusion using the KPG index, a novel 3D classification system for canine impaction.

MATERIALS AND

METHODS

In this cross-sectional study, 74 cone-beam computed tomography (CBCT) images of subjects with palatally impacted canines were collected from one dental radiographic clinic. Impacted canines were assessed and KPG index of difficulty of treatment was calculated for each tooth. Lateral cephalograms corresponding with each CBCT were also traced and analysed. To assess the relationship between the level of treatment difficulty and type of malocclusion, the Chi2 test was used. The Kruskal-Wallis H test was used to assess the difficulty score between the three classes of malocclusion.

RESULTS

There was no correlation between different sagittal skeletal measurements and treatment difficulty of impacted teeth (P>0.05). A positive correlation was shown between KPG index and linear measurements of A to Pn and facial angle (FH-N Pog) (P<0.05). Difficulty of treatment did not differ among various patterns of vertical growth.

CONCLUSION

Treatment of impacted canines is more difficult in patients with maxillary prognathism and it is recommended that these patients be more meticulously evaluated prior to treatment.