Three-dimensional evaluations of the digital casts of morphologic maxillary teeth symmetry in patients with unilateral palatally displaced canines.

INTRODUCTION

The goal of this study was to compare the size and morphologic symmetry of the maxillary teeth in subjects with and without unilateral palatally displaced canines (PDCs).

METHODS

Plaster casts of 38 subjects (mean age 14.75 ± 0.95 y) with unilateral PDCs were selected (study group [SG]) and compared with casts from an age- and sex-matched control group (CG). Then dental casts of both groups were scanned into 3-dimensional (3D) models. Tooth sizes (mesiodistal [MD] and buccolingual [BL] widths and volumes) for SG and CG were measured. Afterward, 3D deviation analysis was carried out with the use of Geomagic Control X software. All of the data were normally distributed according to parametric tests.

RESULTS

All of the maxillary tooth diameters were smaller in SG than in CG. Statistically significant differences (P ≤ 0.001) were obtained when comparing the widths and volumes of the PDC quadrant and the unaffected quadrant of the same patient. Morphologic tooth symmetry by surface-to-surface matching for SG (PDC side vs non-PDC side) and CG (right vs left quadrant) demonstrated significant (P ≤ 0.001) but small differences, except for the lateral upper incisors (71.27%).

CONCLUSIONS

Unlike control subjects, PDC patients showed high mismatching of lateral incisor crowns of ∼30%.