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. 2023 Apr;3(2):93-109.
doi: 10.1016/j.xaor.2023.01.003. Epub 2023 Jan 25.

Clear aligner mandibular advancement in growing patients with Class II malocclusion

Marcela Lima Gurgel  1 , Antonio Carlos de Oliveira Ruellas  1   2 , Jonas Bianchi  3 , James A McNamara Jr  1 , Sandra Tai  4 , Lorenzo Franchi  5 , Romain Deleat-Besson  1 , Celia Le  1 , Candice Logan  1 , Najla Al Turkestani  1   6 , Camila Massaro  7 , Aron Aliaga Del Castillo  8 , Karine Evangelista Martins Arruda  7 , Erika Benavides  9 , Marilia Yatabe  1 , Lucia Cevidanes  1
Affiliations

Clear aligner mandibular advancement in growing patients with Class II malocclusion

Marcela Lima Gurgel et al. AJO DO Clin Companion. 2023 Apr.

Abstract

Treatment effects occurring during Class II malocclusion treatment with the clear aligner mandibular advancement protocol were evaluated in two growing patients: one male (12 years, 3 months) and one female (11 years, 9 months). Both patients presented with full cusp Class II molar and canine relationships. Intraoral scans and cone-beam computed tomography were acquired before treatment and after mandibular advancement. Three-dimensional skeletal and dental long-axis changes were quantified, in which the dental long axis was determined by registering the dental crowns obtained from intraoral scans to the root canals in cone-beam computed tomography scans obtained at the same time points. Class II correction was achieved by a combination of mandibular skeletal and dental changes. A similar direction of skeletal and dental changes was observed in both patients, with downward and forward displacement of the mandible resulting from the growth of the mandibular condyle and ramus. Dental changes in both patients included mesialization of the mandibular posterior teeth with flaring of mandibular anterior teeth. In these two patients, clear aligner mandibular advancement was an effective treatment modality for Class II malocclusion correction with skeletal and dental effects and facial profile improvement.

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Conflict of interest statement

CONFLICTS OF INTEREST All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest, and none were reported.

Figures

Fig 1.
Fig 1.
Patient 1: A, A male patient aged 12 years, 3 months before clear aligner MA treatment; B, Treatment progress after 9 months, 2 weeks of mandibular advancement; C, Skeletal changes before (blue) and after (gray) the mandibular advancement. The top row shows the cranial base superimposition, the middle row shows the maxillary superimposition, and the bottom row shows mandibular regional superimposition. Arrows indicate the direction of displacements, and measurements are shown in millimeters; D, Cephalometric tracing with pretreatment (black) and posttreatment (red) superimpositions. The top row shows the cranial base superimposition, the middle row shows maxillary superimposition, and the bottom row shows mandibular regional superimposition; E, Posttreatment records.
Fig 2.
Fig 2.
Patient 1: Intraoral photographs before clear aligner MA treatment, after mandibular advancement and at the end of treatment. CBCT/IOS merged superimpositions before and after the MA. The side views of the IOSs highlight the initial full Class II occlusion.
Fig 3.
Fig 3.
Patient 1: A, Pretreatment panoramic radiograph; B, Pretreatment lateral cephalogram; C, Posttreatment panoramic radiograph; D, Posttreatment lateral cephalogram.
Fig 4.
Fig 4.
Patient 2: A, A female patient aged 11 years, 9 months before clear aligner MA treatment; B, Treatment progress after 7 months, 3 weeks of mandibular advancement; C, Skeletal changes before (blue) and after (gray) indicate the amount of mandibular advancement. The top row shows cranial base superimposition, the middle row shows maxillary superimposition, and the bottom row shows mandibular regional superimposition. Arrows indicate the direction of displacements, and measurements are shown in millimeters; D, Cephalometric tracing with pretreatment (black) and posttreatment (red) superimpositions; The top row shows the cranial base superimposition, the middle row shows maxillary superimposition, and the bottom row shows mandibular regional superimposition; E, Posttreatment records.
Fig 5.
Fig 5.
Patient 2: Intraoral photographs before clear aligner MA treatment, after mandibular advancement and at the end of treatment. CBCT/IOS merged superimpositions before and after the MA. The side views of the initial IOSs highlight the initial full Class II occlusion.
Fig 6.
Fig 6.
Patient 2: A, Pretreatment panoramic radiograph; B, Pretreatment lateral cephalogram; C, Posttreatment panoramic radiograph; D, Posttreatment lateral cephalogram.
Fig 7.
Fig 7.
A, The clear aligner MA appliance; B, IOS with digital precision wings in the treatment plan for patient 1; C, IOS with digital precision wings in the treatment plan for patient 2.
Fig 8.
Fig 8.
Three-dimensional reconstruction of the digital dental model registration to oriented CBCT scans.
Fig 9.
Fig 9.
Data Storage for Computational and Integration open-access platform tools.
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References

    1. Tulloch JF, Proffit WR, Phillips C. Outcomes in a 2-phase randomized clinical trial of early Class II treatment. Am J Orthod Dentofacial Orthop 2004;125:657–67. - PubMed
    1. Keeling SD, Wheeler TT, King GJ, Garvan CW, Cohen DA, Cabassa S, et al. Anteroposterior skeletal and dental changes after early Class II treatment with bionators and headgear. Am J Orthod Dentofacial Orthop 1998;113:40–50. - PubMed
    1. Ghafari J, Shofer FS, Jacobsson-Hunt U, Markowitz DL, Laster LL. Headgear versus function regulator in the early treatment of Class II, Division 1 malocclusion: a randomized clinical trial. Am J Orthod Dentofacial Orthop 1998;113:51–61. - PubMed
    1. Tulloch JF, Medland W, Tuncay OC. Methods used to evaluate growth modification in Class II malocclusion. Am J Orthod Dentofacial Orthop 1990;98:340–7. - PubMed
    1. Johnston LE Jr.. Growing jaws for fun and profit. A modest proposal. Craniofacial Growth Series 1999;35:63–86.

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