Three-dimensional evaluation of the relationship between dental and basal arch forms in skeletal class II malocclusions

This study aims to investigate the relationship between the dental and basal arch forms of patients with skeletal class II malocclusion using three-dimensional virtual models and to generate the best-fit curve for these arch forms. The mandibular dental casts of 35 skeletal class II patients were taken prior to treatment and were laser scanned. The facial axis (FA) points, which were used to represent the dental arch, and the WALA points, which were used to represent the basal bone, were identified for each tooth from the right first molar to the left first molar. The Pearson correlation coefficients between the intercanine and intermolar widths at the FA and WALA points were determined. Finally, the best-fit curves were generated using the fourth-degree polynomial equation to represent the arch forms. A strong correlation was found between the FA and WALA intermolar widths (r = 0.873). However, a moderate correlation was observed between the FA and WALA intercanine widths (r = 0.534). The difference between