OBJECTIVES

To compare tooth movement achieved, time required for alignment, root resorption, and alveolar bone thickness changes during initial dental alignment between groups treated with 0.012-inch preformed heat-activated or customized nickel titanium (NiTi) archwires.

MATERIALS AND METHODS

Thirty-two subjects (mean age 19.8 ± 1.7 years) with severe crowding of maxillary anterior teeth had premolar extractions and were randomly allocated into control and experimental groups receiving preformed heat-activated and customized NiTi archwires, respectively. Limited field of view cone-beam computed tomographies were taken initially (T) and three months after final alignment (T) to evaluate bone changes. Digital model analysis assessed tooth movement at monthly intervals. Time to achieve alignment was assessed in months. Wilcoxon signed-rank tests and Mann-Whitney U-tests were used to compare changes within and between groups, as appropriate.

RESULTS

Central incisor tooth movement was significantly different (all P ≤ .003) between groups at all time points. T-T showed labial movement (0.75 ± 1.42 mm) in the control group and palatal movement (-0.96 ± 0.41 mm) in the experimental group. The experimental compared to control group showed significantly more canine distal movement (0.60 ± 0.28 mm; P ≤ .049), less labial bone thickness changes ( P ≤ .004), less root resorption of the central and lateral incisors ( P ≤ .007), and a longer time to achieve alignment ( P = .01).

CONCLUSIONS

The experimental group exhibited palatal movement of the central incisors, more canine distal movement with less bone thickness changes, and less root resorption but took more time to achieve alignment than the control group.