In Vivo Comparison of the Efficiency of En-Masse Retraction Using Temporary Anchorage Devices With and Without Orthodontic Appliances on the Posterior Teeth

Abstract

Objective: To compare the effectiveness of en-masse retraction of maxillary anterior teeth using temporary anchorage devices with and without orthodontic appliances on the posterior teeth.Methods:In the study, 20 participants (18.25 ± 4.07 years) meeting the inclusion criteria were randomly divided into 2 groups using the sequentially numbered opaque sealed envelopes method. In group I (control group, n = 10), en-masse retraction was carried out with conventional high hooks soldered to the retraction wire and posterior teeth were included. In group II (experimental group, n = 10), the en-masse retraction was carried out without an orthodontic appliance on posterior teeth and a modified retraction wire was incorporated. In both groups, mini-implants were placed bilaterally between the maxillary second premolar and maxillary first molar, and a retraction force of 6 ounces (180 g) was applied using power chains. Lateral cephalograms and study models were taken before retraction and 4 months after retraction. All statistical analyses were performed with Statistical Package for the Social Sciences software with a statistically significant level of 5%. We used unpaired t-tests for the comparison, and the error of the method was assessed using intraclass correlation coefficients and the Bland–Altman method.Results: The maxillary incisor apex retraction, change in maxillary incisor in the vertical plane, and its inclination showed statistically significant differences (P < .05). The rate of retraction was significantly greater in the experimental group when evaluated clinically and in the study models (P < .05).Conclusion: The rate/amount of retraction evaluated clinically and in the study models was significantly faster/greater when the posterior teeth were not included during anterior retraction. Also, a greater amount of bodily retraction of anterior teeth was achieved.

Keywords

• en-masse retraction
• mini-implants
• without posterior dental anchorage