Three-dimensional analysis of zygomatic change after L-shaped reduction malarplasty with bone setback or resection

The accuracy of virtual surgical planning assisted management for L-shaped reduction malarplasty: A retrospective study

This study aims to evaluate the accuracy of L-shaped reduction malarplasty with bone setback or resection on the zygoma and the mortice and tenon joint structure on the zygomatic arch under the guidance of virtual surgical planning (VSP). Adult patients with zygomatic protrusion or hypertrophy were enrolled and divided. L-shaped reduction malarplasty with or without bone resection and with the mortice and tenon joint structure on the zygomatic arch was conducted either by digital procedures comprising VSP and three-dimensional (3D) printing titanium templates (Group I) or by conventional methods (Group II). Positions of representative landmarks and superimposition models were analyzed by 3D cephalometry. Satisfaction rate and incidences of clinical complications were compared as well. Satisfactory reduction of zygomatic protrusion or hypertrophy was recognized among all 78 patients. Improved symmetry and great surgical accuracy were observed according to the cephalometry analyses. The bone segment movement of virtual plans and actual results in Group I were measured and showed no obvious difference for the inward movement (5.42 ± 0.98 mm vs. 5.33± 0.93 mm, P = 0.6906) and the sagittal overlap (4.77 ± 1.32 mm vs. 4.87± 1.21 mm, P = 0.7386) at the zygoma roots, along with the step length at the long-arm of the L-shaped osteotomy line (2.43 ± 1.11 mm vs. 2.39± 0.89 mm, P = 0.8665). The high resemblance between virtual plans and actual results was depicted via superimposition models. Meanwhile, a higher satisfaction rate (28 in 36, 78% vs. 20 in 42, 48%) and a lower incidence rate of complications (11 in 36, 31% vs. 21 in 42, 50%) were found in Group I. Within the limitations of the study it seems that the application of VSP in reduction malarplasty could significantly contribute to better surgical accuracy and reduced difficulties in the operation, which would be beneficial to patients with zygoma hypertrophy or prominence.

Anti-sagging Method in Reduction Malarplasty: Application of the Bracing System with the Preservation of the Zygomaticus Major Muscle Bony Attachment

BACKGROUND

Cheek drooping after reduction malarplasty remains a concern for patients.

OBJECTIVES

To evaluate the anti-drooping effectiveness of the bracing system technique with the preservation of the zygomaticus major muscle (ZMj) bony attachment and to determine the role of ZMj in anti-drooping.

METHODS

A retrospective analysis was conducted of patients who accepted this method in our department from February 2016 to May 2021. Patients' subjective evaluation and two plastic surgeons' objective assessment of photographs were performed. The pre- and postoperative three-dimensional (3D) ZMj models were reconstructed and compared. ZMj length and tortuosity were also measured from 3D models.

RESULTS

Twenty-two patients (44 ZMjs) met the inclusion criteria. Most patients (21/22, 95.45%) were satisfied with the postoperative appearance without ageing after reduction malarplasty, except for one feeling slightly older after the operation. The objective scoring results showed no deepening of the nasolabial fold in the majority (20/22, 90.91%) of patients. Two patients were one-grade worse, from score 1 to 2. Upward movement of the postoperative ZMj bony attachment was clearly observed compared with the preoperative 3D model. The significantly reduced ZMj tortuosity (p < 0.001) and the slightly increased ZMj length (not significant) after surgery supported the straightening of the ZMj which was also seen in the 3D comparison.

CONCLUSIONS

The bracing system technique with preservation of the bony attachment of the ZMj is an effective and cost-effective anti-sagging method for reduction malarplasty. The ZMj was lifted and straightened after reduction malarplasty, which helped to prevent sagging.

LEVEL OF EVIDENCE IV

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