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. 2023 Sep 1;93(5):524-530.
doi: 10.2319/110422-755.1.

Dimensional changes in the palate associated with Invisalign First System: a pilot study

Junbo Wang, Abdulkadir Bukhari, Sandra K Tai, Bingshuang Zou

Dimensional changes in the palate associated with Invisalign First System: a pilot study

Junbo Wang et al. Angle Orthod. .

Abstract

Objectives: To compare palatal dimensions and molar inclinations after Invisalign First System (IFS) to those in patients treated with slow maxillary expansion (SME) and normal controls.

Materials and methods: Twenty-three mixed dentition patients treated with IFS were gender- and dental age-matched to another two groups: Haas-type SME and control group. The intercanine width (ICW), intermolar width (IMW), palatal surface area (SA), volume (V), and first molar buccolingual inclinations (MI) were measured before (T1) and after (T2) treatment. Analysis of variance was used to compare the differences among the three groups.

Results: The ICW increased significantly by 3.10 mm after IFS, 4.77 mm with SME, and 0.54 mm in controls; the difference among the groups was statistically significant (P < .001). The IMW increased by 1.95 mm in IFS, 4.76 mm in SME, and 0.54 mm in controls, with significant intra- and intergroup differences. Palatal SA and volume increased by 43.50 mm2 and 294.85 mm3 in the IFS group, which differed significantly from SME, but was similar to controls. The right and left MI increased 0.24° and 0.08° buccally, respectively, in the IFS group, which was comparable to controls, while significantly increased buccal MI was observed in the SME group.

Conclusions: IFS expands the upper arch with increased ICW and IMW compared to controls, but the expansion amount is smaller than SME. Unlike SME, IFS has no effects on palatal dimensions and molar inclinations.

Keywords: Invisalign First system; Molar inclination; Palatal dimension; Slow maxillary expansion.

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Figures

Figure 1.
Figure 1.
Landmark identification and measurements of ICW and IMW. ICW indicates intercanine width; IMW, intermolar width.
Figure 2.
Figure 2.
Palatal surface area (A) and volume (B) measurements including anterior (black), middle (light gray), and posterior (dark gray) segments.
Figure 3.
Figure 3.
Illustration of molar buccolingual inclination measurement.
Figure 4.
Figure 4.
Bland-Altman plot of repeated linear (A), areal (B), volumetric (C), and angular (D) measurements.
See this image and copyright information in PMC

References

    1. Garnett BS, Mahood K, Nguyen M, et al. Cephalometric comparison of adult anterior open bite treatment using clear aligners and fixed appliances. Angle Orthod. 2019;89:3–9. - PMC - PubMed
    1. Henick D, Dayan W, Dunford R, Warunek S, Al-Jewair T. Effects of Invisalign (G5) with virtual bite ramps for skeletal deep overbite malocclusion correction in adults. Angle Orthod. 2021;91:164–170. - PMC - PubMed
    1. Dai FF, Xu TM, Shu G. Comparison of achieved and predicted tooth movement of maxillary first molars and central incisors: first premolar extraction treatment with Invisalign. Angle Orthod. 2019;89:679–687. - PMC - PubMed
    1. Cong A, Ruellas ACO, Tai SK, et al. Presurgical orthodontic decompensation with clear aligners. Am J Orthod Dentofacial Orthop. 2022;162:538–553. - PMC - PubMed
    1. Favero R, Volpato A, Favero L. Managing early orthodontic treatment with clear aligners. J Clin Orthod. 2018;52:701–709. - PubMed

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