Are torque values of preadjusted brackets precise?

Abstract

ObjectiveThe aim of the present study was to verify the torque precision of metallic brackets with MBT prescription using the canine brackets as the representative sample of six commercial brands. Material and MethodsTwenty maxillary and 20 mandibular canine brackets of one of the following commercial brands were selected: 3M Unitek, Abzil, American Orthodontics, TP Orthodontics, Morelli and Ortho Organizers. The torque angle, established by reference points and lines, was measured by an operator using an optical microscope coupled to a computer. The values were compared to those established by the MBT prescription. ResultsThe results showed that for the maxillary canine brackets, only the Morelli torque (-3.33º) presented statistically significant difference from the proposed values (-7º). For the mandibular canines, American Orthodontics (-6.34º) and Ortho Organizers (-6.25º) presented statistically significant differences from the standards (-6º). Comparing the brands, Morelli presented statistically significant differences in comparison with all the other brands for maxillary canine brackets. For the mandibular canine brackets, there was no statistically significant difference between the brands. ConclusionsThere are significant variations in torque values of some of the brackets assessed, which would clinically compromise the buccolingual positioning of the tooth at the end of orthodontic treatment.

Study of the Relationship of Smile Esthetics Between Torque and Dental Arch Width of Posterior Teeth in Orthodontics

“…Despite this overall improvement, there was significant variation in the final torque values when analyzed between techniques and within each of them, which is consistent with that observed by authors like Streva et al [10] or Brauchli et al [11].…”

“…Studies like Streva et al [10] agree that the information that fails to express torque can exceed manufacturer estimated values by obtaining lower precision than expected. According Brauchli et al [11] the time of treatment with high diameter archwires could influence the amount of torque expressed 6, but there are still no concrete data in the literature about this topic.…”

Comparative analysis of real and ideal wire-slot play in square and rectangular archwires

“…1 However, the real position of the teeth often differs from that expected at the end of orthodontic treatment, especially in terms of dental inclination (torque). This means the clinician has to resort to special measures to compensate for gaps in the information expressed by the system, for example, with finishing bends.…”

Shear Bond Strength of Metallic Brackets: An In Vitro Stud

“…The meshes of Standard, Ligth and Agile brackets have similar conformations, with small spaces among metal webs, which are welded on the bases of these accessories [21][22][23][24]. However, the sizes of these brackets differ, with Standard being larger than Ligth and Agile, which have similar sizes, highlighting the aesthetics of the fixed orthodontic appliance.…”

“…Regarding Max bracket, according to literature [21,24], body and retentive base form a single structure, with base composed of pins of blasted surfaces and openings for the exit of air during bonding, when pressing the bracket against the dental crown. It is suggested, therefore, that this difference in conformation among metallic meshes of accessories under study, may have contributed to greater adherence of the adhesive to the base of the Max bracket, achieving greater strength.…”