Buccolingual Inclination Control of Upper Central Incisors of Aligners: A Comparison with Conventional and Self-Ligating Brackets

Abstract

Objective The upper incisors torque expression is essential for the orthodontic treatment accuracy. Various orthodontic devices are claimed to have different inclination control capacity. The purpose of this retrospective study was to compare the radiographic buccolingual inclination of upper incisors in patients treated with three different orthodontic techniques. Material and Methods Conventional brackets (Victory, 3M), self-ligating appliances (Damon Q, Ormco), and aligners (Invisalign, Align Technology) were tested. Cephalometric data of 25 patients with similar skeletal and dental pretreatment parameters were collected for each technique. Position changes of upper central incisors were assessed with radiographic evaluation before and after therapy. Three different parameters were considered: 11∧SnaSnp, 11∧Ocl and I+ TVL. All variables were measured before (T0) and after (T1) treatment and their variation over treatment was assessed. Results When evaluating angular measurements, 11∧SnaSnp and 11∧Ocl angles showed the highest numeric variation with conventional brackets. Lowest values were reported with aligners. However, the differences among various techniques were not significant for both angles (P>0.05). Also I+ TVL linear value variation did not show significant differences among the different groups tested (P>0.05). Conclusion Conventional multibrackets appliance showed the highest incisal position variations over treatment, but the differences among various groups were not significantly different.

Effectiveness of clear aligner therapy for orthodontic treatment: A systematic review

“…Also, there was no significant increase in intercanine width in either group. A moderate RoB study showed similar torque control of upper central incisor with aligner and fixed appliance mechanotherapy . Nevertheless, this study used 0.019 × 0.025 inch wire in 0.022 × 0.025 inch slot that itself has torque loss of 10°.…”

“…Of the seven included articles, one is a randomized controlled trial (RCT), and six are retrospective cohort studies . All articles were written in English.…”

“…Five of the covered studies assessed predictability of tooth movement comparing post‐treatment patient models to the predicted digital planned tooth movement models [(ClinCheck ® ) (Vectra software; Canfield Scientific,)]. Two studies compared the clear aligner therapy outcome to the fixed appliance treatment outcome by using lateral cephalograms …”

“…Lombardo et al and Grünheid et al tried to minimize this error (no statistically significant error was observed) by using the occlusal plane and best‐fit algorithms, respectively. Two studies used lateral cephalograms that have been suggested to have limited precision in locating the incisor apex for the outcome assessment. However, inter‐ and intra‐operator errors were not significant in both the studies.…”

“…Sfondrini et al conducted a retrospective study (n = 75) to compare buccolingual inclination (torque) of upper central incisors achieved with power ridges of aligner technology to 0.019 × 0.025 inch stainless steel wire with conventional and self‐ligating brackets. Patients treated with aligners were enrolled between June 2013 and June 2015.…”