Study Model-based Evaluation of Built-in Tip, Torque, and In–out Characteristics of a Third-generation Preadjusted Edgewise Appliance
Rishabh Gupta, Gowdara Shivaprakash, Mala R Manohar, Sonali Sonali
Citation Information :
Gupta R, Shivaprakash G, R Manohar M, Sonali S. Study Model-based Evaluation of Built-in Tip, Torque, and In–out Characteristics of a Third-generation Preadjusted Edgewise Appliance. J Contemp Dent Pract 2018; 19 (1):20-29.
Aim: The aim of the study was to evaluate the clinical effectiveness
of MBT™ preadjusted edgewise appliance (PEA) in terms
of achieving the optimal expression of its built-in characteristics
of tip, torque, and in–out.
Materials and methods: Pretreatment and posttreatment study
models of 20 subjects who received full fixed appliance treatment
involving four first premolar extractions using the MBT™
appliance were measured for tip, torque, and in–out using the
method described by Andrews. Treatment changes were analyzed
statistically, and the posttreatment measurements were
compared with the MBT™ specifications as well as Andrews’
values for the above-mentioned parameters.
Results: Except for the maxillary canines and second premolars,
the built-in tip of MBT™ appliance was nearly fully expressed,
though there was some lack of correlation with Andrews’ values.
Despite the fact that the full amount of torque built into the
MBT™ appliance was not expressed, torque measurements
for all teeth except the maxillary second premolars and the first
molars showed either no statistically significant difference or
were significantly higher than Andrews’ values for these teeth.
In–out readings were lower than both MBT™ and Andrews’
values, but the relative order of crown prominences was similar.
Conclusion and clinical significance: The MBT™ appliance is
thus effective in ensuring a successful treatment result, though
individual adjustments may be necessary for optimal tooth positioning
at the end of the treatment, as with any preadjusted appliance.
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