Effect of Different Bracket Prescriptions on Orthodontic Treatment Outcomes Measured by Three-dimensional Scanning.

Various types of bracket are currently available, and different prescriptions are provided for the same type of tooth. There are no definite criteria, however, on which to base bracket selection. The purpose of this study was to investigate differences in the angulation and inclination of orthodontically aligned teeth when using different prescription brackets. Thirty patients undergoing orthodontic treatment for maxillary protrusion and crowding were enrolled. After orthodontic treatment with a pre-adjusted appliance, angulation and inclination were measured on dental casts obtained from these patients (10 each with 0.022 MBT, 0.022 Roth, or 0.018 Roth brackets). The dental casts were scanned and digitized using a 3-dimensional (3-D) scanner and measured with 3-D model measurement software. A significant difference was observed in the mean angulation of the mandibular canine between the 0.022 MBT (5.81°) and 0.018 Roth groups (9.07°). Greater mesial inclination was observed in the 0.018 Roth group. No significant difference was observed in any of the other regions measured. Differences in bracket prescription showed no clinical influence on treatment outcomes. A significant difference was observed in the mandibular canine (p<0.05), suggesting that consideration is required when selecting brackets.